Commit Graph

622 Commits

Author SHA1 Message Date
Dmitry Konstantinov
7402a3a55a Propagate ref to pool thread cache down in the allocation stack to avoid extra thread local lookup (#10166)
Motivation:
PoolChunk requires a link to a PoolThreadCache to init ByteBuf. Currently the link is retrieved from a thread local: arena.parent.threadCache().
It has some performance cost. At the beginning of the allocation call the PoolThreadCache is already retrieved from the thread local. The reference can be propagated through the calls and used.

Modifications:
Replace second lookup of PoolThreadCache during ByteBuf init by propagation of a reference to PoolThreadCache down in the allocation stack explicitly

Result:
Improve performance of ByteBuf allocation
--Before--
Benchmark                                            (size)  (tokens)  (useThreadCache)  Mode  Cnt    Score   Error  Units
SimpleByteBufPooledAllocatorBenchmark.getAndRelease     123         0              true  avgt   20   57.112 ± 1.004  ns/op
SimpleByteBufPooledAllocatorBenchmark.getAndRelease     123       100              true  avgt   20  222.827 ± 1.307  ns/op

--After--
Benchmark                                            (size)  (tokens)  (useThreadCache)  Mode  Cnt    Score   Error  Units
SimpleByteBufPooledAllocatorBenchmark.getAndRelease     123         0              true  avgt   20   50.732 ± 1.321  ns/op
SimpleByteBufPooledAllocatorBenchmark.getAndRelease     123       100              true  avgt   20  216.892 ± 3.806  ns/op
2020-04-06 08:07:44 +02:00
Dmitry Konstantinov
dc69c04434 Replace usage() with freeBytes() in thresholds within hot paths of PoolChunkList (#10141)
Motivation:
PoolChunk.usage() method has non-trivial computations. It is used currently in hot path methods invoked when an allocation and de-allocation are happened.
The idea is to replace usage() output comparison against percent thresholds by Chunk.freeBytes plain comparison against absolute thresholds. In such way the majority of computations from the threshold conditions are moved to init logic.

Modifications:
Replace PoolChunk.usage() conditions in PoolChunkList with equivalent conditions for PoolChunk.freeBytes()

Result:
Improve performance of allocation and de-allocation of ByteBuf from normal size cache pool
2020-03-31 22:11:42 +02:00
Dmitry Konstantinov
71b7dbc009 Optimize log2 in PoolThreadCache (#10128)
Motivation:
The current implementation of log2 in PoolThreadCache uses a loop and less efficient than an version based on Integer.numberOfLeadingZeros (intrinsic).

Modifications:
Replace the current log2 implementation in PoolThreadCache with a version based on Integer.numberOfLeadingZeros

Result:
It can improve performance slightly during allocation and de-allocation of ByteBuf using pooled allocator.
2020-03-24 11:14:08 +01:00
Norman Maurer
8ab4adcc56 FixedCompositeByteBuf.isDirect() may return wrong value when constructed with empty array (#10005)
Motivation:

FixedCompositeByteBuf.isDirect() should return the same value as EMPTY_BUFFER.isDirect() when constructed via an empty array

Modifications:

- Return correct value when constructed via empty array.
- Add unit test

Result:

FixedCompositeByteBuf.isDirect() returns correct value
2020-02-08 17:05:44 +01:00
Norman Maurer
0d4af6d9da Fix incorrect property name in PooledByteBufAllocator
Motivation:

We hat a typo in the property name that is used in PooledByteBufAllocator.

Modifications:

Change from "...allocation.." to "...allocator.."

Result:

More consistent property naming
2020-02-05 14:40:08 +01:00
Norman Maurer
6a43807843
Use lambdas whenever possible (#9979)
Motivation:

We should update our code to use lamdas whenever possible

Modifications:

Use lambdas when possible

Result:

Cleanup code for Java8
2020-01-30 09:28:24 +01:00
Nick Hill
727f03755c Fix BufferOverflowException during non-Unsafe PooledDirectByteBuf resize (#9912)
Motivation

Recent optimization #9765 introduced a bug where the native indices of
the internal reused duplicate nio buffer are not properly reset prior to
using it to copy data during a reallocation operation. This can result
in BufferOverflowExceptions thrown during ByteBuf capacity changes.

The code path in question applies only to pooled direct buffers when
Unsafe is disabled or not available.

Modification

Ensure ByteBuffer#clear() is always called on the reused internal nio
buffer prior to returning it from PooledByteBuf#internalNioBuffer()
(protected method); add unit test that exposes the bug.

Result

Fixes #9911
2020-01-11 06:05:32 +01:00
Sergey Skrobotov
f10bee9057 Change DefaultByteBufHolder.equals() to treat instances of different classes as not equal (#9855)
# Motivation:
`DefaultByteBufHolder.equals()` considers another object equal if it's an instance of `ByteBufferHolder` and if the contents of two objects are equal. However, the behavior of `equals` method is not a part of the `ByteBufHolder` contract so `DefaultByteBufHolder`'s version may be causing violation of the symmetric property if other classes have different logic.
There are already a few classes that are affected by this: `DefaultHttp2GoAwayFrame`, `DefaultHttp2UnknownFrame`, and `SctpMessage` are all overriding `equals` method breaking the symmetric property.
Another effect of this behavior is that all instances with empty data are considered equal. That may not be desireable in the situations when instances are created for predefined constants, e.g. `FullBulkStringRedisMessage.NULL_INSTANCE` and `FullBulkStringRedisMessage.EMPTY_INSTANCE` in `codec-redis`. 

# Modification:
Make `DefaultByteBufHolder.equals()` implementation only work for the objects of the same class.

# Result:
- The symmetric property of the `equals` method is restored for the classes in question.
- Instances of different classes are not considered equal even if the content of the data they hold are the same.
2019-12-10 11:30:23 +01:00
Nick Hill
4a5712f8d9 Minor simplifications/optimizations to AbstractByteBuf methods (#9845)
Motivation

While working on other changes I noticed some opportunities to
streamline a few things in AbstractByteBuf.

Modifications

- Avoid duplicate ensureAccessible() checks in discard(Some)ReadBytes()
and ensureWritable0(int) methods
- Simplify ensureWritable0(int) logic
- Make some conditional checks more concise

Result

Cleaner, possibly faster code
2019-12-05 11:51:02 +01:00
Nick Hill
c6bdc2b7dc Reduce ByteBuffer duplication when resizing pooled direct ByteBufs (#9765)
Motivation:

Currently when use of Unsafe is disabled and an internal reallocation is
performed for a direct PooledByteBuf, a one-off temporary duplicate is
made of the source and destination backing nio buffers so that the
copy can be done in a threadsafe manner.

The need for this can be reduced by sharing the temporary duplicate
buffer that is already stored in the corresponding destination
PooledByteBuf instance.

Modifications:

Have PoolArena#memoryCopy(...) take the destination PooledByteBuf
instead of the underlying mem reference and offset, and use
internalNioBuffer() to obtain/initialize a reusable duplicate of the
backing nio buffer.

Result:

Fewer temporary allocations when resizing direct pooled ByteBufs in the
non-Unsafe case
2019-11-16 11:27:03 -08:00
Nick Hill
625981a296 Introduce ByteBuf#isContiguous() method (#9735)
Motivation

There's currently no way to determine whether an arbitrary ByteBuf
behaves internally like a "singluar" buffer or a composite one, and this
can be important to know when making decisions about how to manipulate
it in an efficient way.

An example of this is the ByteBuf#discardReadBytes() method which
increases the writable bytes for a contiguous buffer (by readerIndex)
but does not for a composite one.

Unfortunately !(buf instanceof CompositeByteBuf) is not reliable, since
for example this will be true in the case of a sliced CompositeByteBuf
or some third-party composite implementation.

isContiguous was chosen over isComposite since we want to assume "not
contiguous" in the unknown/default case - the doc will it clear that
false does not imply composite.

Modifications

- Add ByteBuf#isContiguous() which returns true by default
- Override the "concrete" ByteBuf impls to return true and ensure
wrapped/derived impls delegate it appropriately
- Include some basic unit tests

Result

Better assumptions/decisions possible when manipulating arbitrary
ByteBufs, for example when combining/cumulating them.
2019-11-06 12:07:00 +01:00
Norman Maurer
4be554a21f Hide Recycler implemention to allow experimenting with different implementions of an Object pool (#9715)
Motivation:

At the moment we directly extend the Recycler base class in our code which makes it hard to experiment with different Object pool implementation. It would be nice to be able to switch from one to another by using a system property in the future. This would also allow to more easily test things like https://github.com/netty/netty/pull/8052.

Modifications:

- Introduce ObjectPool class with static method that we now use internally to obtain an ObjectPool implementation.
- Wrap the Recycler into an ObjectPool and return it for now

Result:

Preparation for different ObjectPool implementations
2019-10-26 09:43:21 +02:00
Nick Hill
53183ae1ab Change javadoc of ByteBuf#indexOf(...) to match its behaviour (#9679)
Motivation

Currently doc != code and so one needs to change. Though behaviour as
currently documented might be more intuitive, we don't want to break
anyone so will adjust the doc instead. See #9503 for discussion.

Modifications

Correct the javadoc of indexOf(...) method in ByteBuf abstract class.

Results

Correct javadoc
2019-10-25 08:43:52 +02:00
Nick Hill
b08bbd4c20 Fix for incorrect values from CompositeByteBuf#component(int) (#9525)
Motivation

This is a "simpler" alternative to #9416 which fixes the same
CompositeByteBuf bugs described there, originally reported by @jingene
in #9398.

Modifications
- Add fields to Component class for the original buffer along with its
adjustment, which may be different to the already-stored unwrapped
buffer. Use it in appropriate places to ensure correctness and
equivalent behaviour to that prior to the earlier optimizations
- Add comments explaining purpose of each of the Component fields
- Unwrap more kinds of buffers in newComponent method to extend scope of
the existing indirection-reduction optimization
- De-duplicate common buffer consolidation logic
- Unit test for the original bug provided by @jingene

Result
- Correct behaviour / fixed bugs
- Some code deduplication / simplification
- Unwrapping optimization applied to more types of buffers

The downside is increased mem footprint from the two new fields, and
additional allocations in some specific cases, though those should be
rare.


Co-authored-by: jingene <jingene0206@gmail.com>
2019-09-02 13:52:47 +02:00
Norman Maurer
05dd1f05d5 Reduce GC produced by AbstractByteBuf.indexOf(..) implementation (#9502)
Motivation:

AbstractByteBuf.indexOf(...) currently delegates to ByteBufUtils.indexOf(...) which will create a new ByteBufProcessor on each call. This is done to reduce overhead of bounds-checks. Unfortunally while this reduces bounds checks it produces a lot of GC. We can just implement our own version in AbstractByteBuf which makes use of _getByte(...) and so does no bound checks as well but also not need to create any garbage.

Modifications:

Write optimized implementation of indexOf(...) for AbstractByteBuf

Result:

Fixes https://github.com/netty/netty/issues/9499.
2019-08-24 11:48:35 +00:00
Nick Hill
f673ba36a0 Don't zero non-readable buffer regions when capacity is decreased (#9427)
Motivation

region is preserved when capacity is increased, not just the readable
part. The behaviour is still different however when the capacity is
_decreased_ - data outside the currently-readable region is zeroed.

Modifications

Update ByteBuf capacity(int) implementations to also copy the whole
buffer region when the new capacity is less than the current capacity.

Result

Consistent behaviour of ByteBuf#capacity(int) regardless of whether the
new capacity is greater than or less than the current capacity.
2019-08-16 08:28:33 +02:00
Nick Hill
bc22bfa320 Use alloc().heapBuffer(...) to allocate new heap buffer.
Motivation

Underlying array allocations in UnpooledHeapByteBuf are intended be done
via the protected allocateArray(int) method, so that they can be tracked
and/or overridden by subclasses, for example
UnpooledByteBufAllocator$InstrumentedUnpooledHeapByteBuf or #8015. But
it looks like an explicit allocation was missed in the copy(int,int)
method.

Modification

Just use alloc().heapBuffer(...) for the allocation

Result

No possibility of "missing" array allocations when ByteBuf#copy is used.
2019-08-13 10:52:52 +02:00
Nick Hill
dcd145864a Fix ByteBufUtil#writeUtf8 subsequence split surrogate edge-case bug (#9437)
Motivation:

#9224 introduced overrides of ByteBufUtil#writeUtf8(...) and related
methods to operate on a sub-CharSequence directly to save having to
allocate substrings, but it missed an edge case where the subsequence
does not extend to the end of the CharSequence and the last char in the
sequence is a high surrogate.

Due to the catch-IndexOutOfBoundsException optimization that avoids an
additional bounds check, it would be possible to read past the specified
end char index and successfully decode a surrogate pair which would
otherwise result in a '?' byte being written.

Modifications:

- Check for end-of-subsequence before reading next char after a high
surrogate is encountered in the
writeUtf8(AbstractByteBuf,int,CharSequence,int,int) and
utf8BytesNonAscii methods
- Add unit test for this edge case

Result:

Bug is fixed.

This removes the bounds-check-avoidance optimization but it does not
appear to have a measurable impact on benchmark results, including when
the char sequence contains many surrogate pairs (which should be rare in
any case).
2019-08-10 20:54:43 +02:00
Norman Maurer
f0afd7cfcd Correctly take length of ByteBufInputStream into account for readLine… (#9310)
* Correctly take length of ByteBufInputStream into account for readLine() / readByte()

Motivation:

ByteBufInputStream did not correctly take the length into account when validate bounds for readLine() / readByte() which could lead to read more then allowed.

Modifications:

- Correctly take length into account
- Add unit tests
- Fix existing unit test

Result:

Correctly take length of ByteBufInputStream into account.
Related to https://github.com/netty/netty/pull/9306.
2019-07-01 20:55:47 +02:00
xiaoheng1
c0f1e9bd21 Fix public int read() throws IOException method exceeds the limit of length (#9306)
Motivation:

buffer.isReadable() should not be used to limit the amount of data that can be read as the amount may be less then was is readable.

Modification:

- Use  available() which takes the length into account
- Add unit test

Result:

Fixes https://github.com/netty/netty/issues/9305
2019-07-01 15:58:05 +02:00
秦世成
1454c3a777 Fix the issue of incorrectly calculating the number of dump lines when using PrettyDump in ByteBufUtil (#9304)
Motivation:

Fix the issue of incorrectly calculating the number of dump rows when using prettyHexDumpmethod in ByteBufUtil. The way to find the remainder is either length % 16 or length & 15

Modification:

Fixed the way to calculate the remainder

Result:

Fixed #9301
2019-07-01 08:36:00 +02:00
jimin
78adeb5408 All override methods must be added @override (#9285)
Motivation:

Some methods that either override others or are implemented as part of implementation an interface did miss the `@Override` annotation

Modifications:

Add missing `@Override`s

Result:

Code cleanup
2019-06-27 13:52:06 +02:00
Norman Maurer
eae9492c40 EmptyByteBuf.getCharSequence(0,...) must return empty String (#9272)
Motivation:

At the moment EmptyByteBuf.getCharSequence(0,...) will return null while it must return a "".

Modifications:

- Let EmptyByteBuf.getCharSequence(0,...) return ""
- Add unit test

Result:

Fixes https://github.com/netty/netty/issues/9271.
2019-06-24 21:09:52 +02:00
Nick Hill
c61fa9be70 Subsequence versions of ByteBufUtil#writeUtf8(...) methods (#9224)
Motivation

It would be useful to be able to write UTF-8 encoded subsequence of
CharSequence characters to a ByteBuf without needing to create a
temporary object via CharSequence#subSequence().

Modification

Add overloads of ByteBufUtil writeUtf8, reserveAndWriteUtf8 and
utf8Bytes methods which take explicit subsequence bounds.

Result

More efficient writing of substrings to byte buffers possible
2019-06-21 14:06:34 +02:00
Nick Hill
ea2e4a7b3d De-duplicate PooledByteBuf implementations (#9120)
Motivation

There's quite a lot of duplicate/equivalent logic across the various
concrete ByteBuf implementations. We could take this even further but
for now I've focused on the PooledByteBuf sub-hierarchy.

Modifications

- Move common logic/methods into existing PooledByteBuf abstract
superclass
- Shorten PooledByteBuf.capacity(int) method implementation

Result

Less code to maintain
2019-06-19 20:50:57 +02:00
Nick Hill
4ba75b99af De-duplicate UnpooledDirectByteBuf/UnpooledUnsafeDirectByteBuf (#9085)
Motivation

While digging around looking at something else I noticed that these
share a lot of logic and it would be nice to reduce that duplication.

Modifications

Have UnpooledUnsafeDirectByteBuf extend UnpooledDirectByteBuf and make
adjustments to ensure existing behaviour remains unchanged.

The most significant addition needed to UnpooledUnsafeDirectByteBuf was
re-overriding the getPrimitive/setPrimitive methods to revert back to
the AbstractByteBuf versions which include bounds checks
(UnpooledDirectByteBuf excludes these as an optimization, relying on
those done by underlying ByteBuffer).

Result

~200 fewer lines, less duplicate logic.
2019-06-03 13:15:43 +02:00
Idel Pivnitskiy
b5ff56b6ee Make UnpooledUnsafeHeapByteBuf class public (#9184)
Motivation:

1. Users will be able to use an optimized version of
`UnpooledHeapByteBuf` and override behavior of methods if required.
2. Consistency with `UnpooledDirectByteBuf`, `UnpooledHeapByteBuf`, and
`UnpooledUnsafeDirectByteBuf`.

Modifications:

- Add `public` access modifier to `UnpooledUnsafeHeapByteBuf` class and
ctor;

Result:

Public access for optimized version of `UnpooledHeapByteBuf`.
2019-05-31 07:04:52 +02:00
Nick Hill
1e575d7389 Fix redundant or missing checks and other inconsistencies in ByteBuf impls (#9119)
Motivation

There are a few minor inconsistencies / redundant operations in the
ByteBuf implementations which would be good to fix.

Modifications

- Unnecessary ByteBuffer.duplicate() performed in
CompositeByteBuf.nioBuffer(int,int)
- Add missing checkIndex(...) check to
ReadOnlyByteBufferBuf.nioBuffer(int,int)
- Remove duplicate bounds check in
ReadOnlyByteBufferBuf.getBytes(int,byte[],int,int)
- Omit redundant bounds check in
UnpooledHeapByteBuf.getBytes(int,ByteBuffer)

Result

More consistency and slightly less overhead
2019-05-27 15:32:42 +02:00
Nick Hill
4fa7b99da2 Introduce ByteBuf.maxFastWritableBytes() method (#9086)
Motivation

ByteBuf capacity is automatically increased as needed up to maxCapacity
when writing beyond the buffer's current capacity. However there's no
way to tell in general whether such an increase will result in a
relatively costly internal buffer re-allocation.

For unpooled buffers it always does, in pooled cases it depends on the
size of the associated chunk of allocated memory, which I don't think is
currently exposed in any way.

It would sometimes be useful to know where this limit is when making
external decisions about whether to reuse or preemptively reallocate.

It would also be advantageous to take this limit into account when
auto-increasing the capacity during writes, to defer such reallocation
until really necessary.

Modifications

Introduce new AbstractByteBuf.maxFastWritableBytes() method which will
return a value >= writableBytes() and <= maxWritableBytes().

Make use of the new method in the sizing decision made by the
AbstractByteBuf.ensureWritable(...) methods.

Result

Less reallocation/copying.
2019-05-22 20:11:56 +02:00
Nick Hill
d29f91540d Fix possible unsafe sharing of internal NIO buffer in CompositeByteBuf (#9169)
Motivation

A small thread-safety bug was introduced during the internal
optimizations of ComponentByteBuf made a while back in #8437. When there
is a single component which was added as a slice,
internalNioBuffer(int,int) will currently return the unwrapped slice's
un-duplicated internal NIO buffer. This is not safe since it could be
modified concurrently with other usage of that parent buffer.

Modifications

Delegate internalNioBuffer to nioBuffer in this case, which returns a
duplicate. This matches what's done in derived buffers in general
(for the same reason). Add unit test.

Result

Fixed possible thread-safety bug
2019-05-22 11:07:27 +02:00
Tim Brooks
e4ef8f6ff3 Prefer direct io buffers if direct buffers pooled (#9167)
Motivation

Direct buffers are normally preferred when interfacing with raw
sockets. Currently netty will only return direct io buffers (for reading
from a channel) when a platform has unsafe. However, this is
inconsistent with the write-side (filterOutboundMessage) where a direct
byte buffer will be returned if pooling is enabled. This means that
environments without unsafe (and no manual netty configurations) end up
with many pooled heap byte buffers for reading, many pooled direct byte
buffers for writing, and jdk pooled byte buffers (for reading).

Modifications

This commit modifies the AbstractByteBufAllocator to return a direct
byte buffer for io handling when the platform has unsafe or direct byte
buffers are pooled.

Result:

Use direct buffers when direct buffers are pooled for IO.
2019-05-22 07:33:06 +02:00
Nick Hill
5e786e549e Fix incorrect behavior of ReadOnlyByteBufferBuf.getBytes(int,ByteBuffer) (#9125)
* Fix incorrect behavior of ReadOnlyByteBufferBuf.getBytes(int,ByteBuffer)

Motivation

It currently will succeed when the destination is larger than the source
range, but the ByteBuf javadoc states this should be a failure, as is
the case with all the other implementations.

Modifications

- Fix logic to fail the bounds check in this case
- Remove explicit null check which isn't done in any equivalent method
- Add unit test

Result

More correct/consistent behaviour
2019-05-13 07:03:10 +02:00
Norman Maurer
7e6d1bbcfd Fix regression in CompositeByteBuf.discard*ReadBytes() (#9068)
Motivation:

1f93bd3 introduced a regression that could lead to not have the lastAccessed field correctly null'ed out when the endOffset of the internal Component == CompositeByteBuf.readerIndex()

Modifications:

- Correctly null out the lastAccessed field in any case
- Add unit tests

Result:

Fixes regression in CompositeByteBuf.discard*ReadBytes()
2019-04-17 18:03:29 +02:00
Nick Hill
e75b7edaa3 Centralize internal reference counting logic (#8614)
Motivation

AbstractReferenceCounted and AbstractReferenceCountedByteBuf contain
duplicate logic for managing the volatile refcount in an optimized and
consistent manner, which increased in complexity in #8583. It's possible
to extract this into a common helper class now that all access is via an
AtomicIntegerFieldUpdater.

Modifications

- Move duplicate logic into a shared ReferenceCountUpdater class
- Incorporate some additional simplification for the most common single
increment/decrement cases (fewer checks/operations)

Result

Less code duplication, better encapsulation of the "non-trivial"
internal volatile refcount manipulation
2019-04-09 16:23:15 +02:00
Nick Hill
1f93bd36b6 CompositeByteBuf optimizations and new addFlattenedComponents method (#8939)
Motivation:

The CompositeByteBuf discardReadBytes / discardReadComponents methods are currently quite inefficient, including when there are no read components to discard. We would like to call the latter more frequently in ByteToMessageDecoder#COMPOSITE_CUMULATOR.

In the same context it would be beneficial to perform a "shallow copy" of a composite buffer (for example when it has a refcount > 1) to avoid having to allocate and copy the contained bytes just to obtain an "independent" cumulation.

Modifications:

- Optimize discardReadBytes() and discardReadComponents() implementations (start at first comp rather than performing a binary search for the readerIndex).
- New addFlattenedComponents(boolean,ByteBuf) method which performs a shallow copy if the provided buffer is also composite and avoids adding any empty buffers, plus unit test.
- Other minor optimizations to avoid unnecessary checks.

Results:

discardReadXX methods are faster, composite buffers can be easily appended without deepening the buffer "tree" or retaining unused components.
2019-04-08 20:55:19 +02:00
Norman Maurer
1eabb752c0 Fix NPE that was encounter by debugger (will never happen in real code). (#8992)
Motivation:

We synchronize on the chunk.arena when produce the String returned by PoolSubpage.toString() which may raise a NPE when chunk == null. Chunk == null for the head of the linked-list and so a NPE may raised by a debugger. This NPE can never happen in real code tho as we never access toString() of the head.

Modifications:

Add null checks and so fix the possible NPE

Result:

No NPE when using a debugger and inspect the PooledByteBufAllocator.
2019-04-01 19:44:45 +02:00
Norman Maurer
78c4abbfb7
Change default of io.netty.allocator.useCacheForAllThreads to false (#8991)
Motivation:

We currently use a thread local cache for all threads which often is suprising to users as it may result in a lot of memory usage if they allocate buffers from outside the EventLoop in different threads. We should better not do this by default to keep suprises to a minimum. Users that need the performance and know what they are doing can still change this.

Modifications:

Change io.netty.allocator.useCacheForAllThreads to false by default

Result:

Related to https://github.com/netty/netty/issues/8536.
2019-04-01 19:43:19 +02:00
Norman Maurer
ab7accb2de Don't try to put back MemoryRegionCache.Entry objects into the Recycler when recycled because of a finalizer. (#8955)
Motivation:

In MemoryRegionCache.Entry we use the Recycler to reduce GC pressure and churn. The problem is that these will also be recycled when the PoolThreadCache is collected and finalize() is called. This then can have the effect that we try to load class but the WebApp is already stoped.

This will produce an stacktrace like this on Tomcat:

```
19-Mar-2019 15:53:21.351 INFO [Finalizer] org.apache.catalina.loader.WebappClassLoaderBase.checkStateForResourceLoading Illegal access: this web application instance has been stopped already. Could not load [java.util.WeakHashMap]. The following stack trace is thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access.
 java.lang.IllegalStateException: Illegal access: this web application instance has been stopped already. Could not load [java.util.WeakHashMap]. The following stack trace is thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access.
	at org.apache.catalina.loader.WebappClassLoaderBase.checkStateForResourceLoading(WebappClassLoaderBase.java:1383)
	at org.apache.catalina.loader.WebappClassLoaderBase.checkStateForClassLoading(WebappClassLoaderBase.java:1371)
	at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1224)
	at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1186)
	at io.netty.util.Recycler$3.initialValue(Recycler.java:233)
	at io.netty.util.Recycler$3.initialValue(Recycler.java:230)
	at io.netty.util.concurrent.FastThreadLocal.initialize(FastThreadLocal.java:188)
	at io.netty.util.concurrent.FastThreadLocal.get(FastThreadLocal.java:142)
	at io.netty.util.Recycler$Stack.pushLater(Recycler.java:624)
	at io.netty.util.Recycler$Stack.push(Recycler.java:597)
	at io.netty.util.Recycler$DefaultHandle.recycle(Recycler.java:225)
	at io.netty.buffer.PoolThreadCache$MemoryRegionCache$Entry.recycle(PoolThreadCache.java:478)
	at io.netty.buffer.PoolThreadCache$MemoryRegionCache.freeEntry(PoolThreadCache.java:459)
	at io.netty.buffer.PoolThreadCache$MemoryRegionCache.free(PoolThreadCache.java:430)
	at io.netty.buffer.PoolThreadCache$MemoryRegionCache.free(PoolThreadCache.java:422)
	at io.netty.buffer.PoolThreadCache.free(PoolThreadCache.java:279)
	at io.netty.buffer.PoolThreadCache.free(PoolThreadCache.java:270)
	at io.netty.buffer.PoolThreadCache.free(PoolThreadCache.java:241)
	at io.netty.buffer.PoolThreadCache.finalize(PoolThreadCache.java:230)
	at java.lang.System$2.invokeFinalize(System.java:1270)
	at java.lang.ref.Finalizer.runFinalizer(Finalizer.java:102)
	at java.lang.ref.Finalizer.access$100(Finalizer.java:34)
	at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:217)
```

Beside this we also need to ensure we not try to lazy load SizeClass when the finalizer is used as it may not be present anymore if the ClassLoader is already destroyed.

This would produce an error like:

```
20-Mar-2019 11:26:35.254 INFO [Finalizer] org.apache.catalina.loader.WebappClassLoaderBase.checkStateForResourceLoading Illegal access: this web application instance has been stopped already. Could not load [io.netty.buffer.PoolArena$1]. The following stack trace is thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access.
 java.lang.IllegalStateException: Illegal access: this web application instance has been stopped already. Could not load [io.netty.buffer.PoolArena$1]. The following stack trace is thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access.
	at org.apache.catalina.loader.WebappClassLoaderBase.checkStateForResourceLoading(WebappClassLoaderBase.java:1383)
	at org.apache.catalina.loader.WebappClassLoaderBase.checkStateForClassLoading(WebappClassLoaderBase.java:1371)
	at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1224)
	at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1186)
	at io.netty.buffer.PoolArena.freeChunk(PoolArena.java:287)
	at io.netty.buffer.PoolThreadCache$MemoryRegionCache.freeEntry(PoolThreadCache.java:464)
	at io.netty.buffer.PoolThreadCache$MemoryRegionCache.free(PoolThreadCache.java:429)
	at io.netty.buffer.PoolThreadCache$MemoryRegionCache.free(PoolThreadCache.java:421)
	at io.netty.buffer.PoolThreadCache.free(PoolThreadCache.java:278)
	at io.netty.buffer.PoolThreadCache.free(PoolThreadCache.java:269)
	at io.netty.buffer.PoolThreadCache.free(PoolThreadCache.java:240)
	at io.netty.buffer.PoolThreadCache.finalize(PoolThreadCache.java:229)
	at java.lang.System$2.invokeFinalize(System.java:1270)
	at java.lang.ref.Finalizer.runFinalizer(Finalizer.java:102)
	at java.lang.ref.Finalizer.access$100(Finalizer.java:34)
	at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:217)
```

Modifications:

- Only try to put the Entry back into the Recycler if the PoolThredCache is not destroyed because of the finalizer.
- Only try to access SizeClass if not triggered by finalizer.

Result:

No IllegalStateException anymoe when a webapp is reloaded in Tomcat that uses netty and uses the PooledByteBufAllocator.
2019-03-22 12:16:53 +01:00
Nick Hill
a71e33ae35 Fix possible ByteBuf leak when CompositeByteBuf is resized (#8946)
Motivation:

The special case fixed in #8497 also requires that we keep a derived slice when trimming components in place, as done by the capacity(int) and discardReadBytes() methods.

Modifications:

Ensure that we keep a ref to trimmed components' original retained slice in capacity(int) and discardReadBytes() methods, so that it is released properly when the they are later freed. Add unit test which fails prior to the fix.

Result:

Edge case leak is eliminated.
2019-03-22 11:18:28 +01:00
Norman Maurer
9681842d54 Allow to automatically trim the PoolThreadCache in a timely interval (#8941)
Motivation:

PooledByteBufAllocator uses a PoolThreadCache per Thread that allocates / deallocates to minimize the performance overhead. This PoolThreadCache is trimmed after X allocations to free up buffers that are not allocated for a long time. This works out quite well when the app continues to allocate but fails if the app stops to allocate frequently (for whatever reason) and so a lot of memory is wasted and not given back to the arena / freed.

Modifications:

- Add a ThreadExecutorMap that offers multiple methods that wrap Runnable / ThreadFactory / Executor and allow to call ThreadExecutorMap.currentEventExecutor() to get the current executing EventExecutor for the calling Thread.
- Use these methods in the constructors of our EventExecutor implementations (which also covers the EventLoop implementations)
- Add io.netty.allocator.cacheTrimIntervalMillis system property which can be used to specify a fixed rate / interval on which we should try to trim the PoolThreadCache for a EventExecutor that allocates.
- Add PooledByteBufAllocator.trimCurrentThreadCache() to allow the user to trim the cache of the calling thread manually.
- Add testcases
- Introduce FastThreadLocal.getIfExists()

Result:

Allow to better / more frequently trim PoolThreadCache and so give back memory to the area / system.
2019-03-22 11:17:40 +01:00
Nick Hill
35161ad174 Further reduce ensureAccessible() overhead (#8895)
Motivation:

This PR fixes some non-negligible overhead discovered in the ByteBuf
accessibility (non-zero refcount) checking. The cause turned out to be
mostly twofold:
- Unnecessary operations used to calculate the refcount from the "raw"
encoded int field value
- Call stack depths exceeding the default limit for inlining, in some
places (CompositeByteBuf in particular)

It's a follow-on from #8882 which uses the maxCapacity field for a
simpler non-negative check. The performance gap between these two
variants appears to be _mostly_ closed, but there's one exception which
may warrant further analysis.

Modifications:

- Replace ABB.internalRefCount() with ByteBuf.isAccessible(), the
default still checks for non-zero refCnt()
- Just test for parity of raw refCnt instead of converting to "real",
with fast-path for specific small values
- Make sure isAccessible() is delegated by derived/wrapper ByteBufs
- Use existing freed flag in CompositeByteBuf for faster isAccessible()
- Manually inline some calls in methods like CompositeByteBuf.setLong()
and AbstractReferenceCountedByteBuf.isAccessible() to reduce stack
depths (to ensure default inlining limit isn't hit)
- Add ByteBufAccessBenchmark which is an extension of
UnsafeByteBufBenchmark (maybe latter could now be removed)

Results:

Before:

Benchmark   (bufferType)  (checkAccessible)  (checkBounds)   Mode  Cnt
Score          Error  Units
readBatch         UNSAFE               true           true  thrpt   30
84524972.863 ±   518338.811  ops/s
readBatch   UNSAFE_SLICE               true           true  thrpt   30
38608795.037 ±   298176.974  ops/s
readBatch           HEAP               true           true  thrpt   30
80003697.649 ±   974674.119  ops/s
readBatch      COMPOSITE               true           true  thrpt   30
18495554.788 ±   108075.023  ops/s
setGetLong        UNSAFE               true           true  thrpt   30
247069881.578 ± 10839162.593  ops/s
setGetLong  UNSAFE_SLICE               true           true  thrpt   30
196355905.206 ±  1802420.990  ops/s
setGetLong          HEAP               true           true  thrpt   30
245686644.713 ± 11769311.527  ops/s
setGetLong     COMPOSITE               true           true  thrpt   30
83170940.687 ±   657524.123  ops/s
setLong           UNSAFE               true           true  thrpt   30
278940253.918 ±  1807265.259  ops/s
setLong     UNSAFE_SLICE               true           true  thrpt   30
202556738.764 ± 11887973.563  ops/s
setLong             HEAP               true           true  thrpt   30
280045958.053 ±  2719583.400  ops/s
setLong        COMPOSITE               true           true  thrpt   30
121299806.002 ±  2155084.707  ops/s


After:

Benchmark   (bufferType)  (checkAccessible)  (checkBounds)   Mode  Cnt
Score          Error  Units
readBatch         UNSAFE               true           true  thrpt   30
101641801.035 ±  3950050.059  ops/s
readBatch   UNSAFE_SLICE               true           true  thrpt   30
84395902.846 ±  4339579.057  ops/s
readBatch           HEAP               true           true  thrpt   30
100179060.207 ±  3222487.287  ops/s
readBatch      COMPOSITE               true           true  thrpt   30
42288494.472 ±   294919.633  ops/s
setGetLong        UNSAFE               true           true  thrpt   30
304530755.027 ±  6574163.899  ops/s
setGetLong  UNSAFE_SLICE               true           true  thrpt   30
212028547.645 ± 14277828.768  ops/s
setGetLong          HEAP               true           true  thrpt   30
309335422.609 ±  2272150.415  ops/s
setGetLong     COMPOSITE               true           true  thrpt   30
160383609.236 ±   966484.033  ops/s
setLong           UNSAFE               true           true  thrpt   30
298055969.747 ±  7437449.627  ops/s
setLong     UNSAFE_SLICE               true           true  thrpt   30
223784178.650 ±  9869750.095  ops/s
setLong             HEAP               true           true  thrpt   30
302543263.328 ±  8140104.706  ops/s
setLong        COMPOSITE               true           true  thrpt   30
157083673.285 ±  3528779.522  ops/s

There's also a similar knock-on improvement to other benchmarks (e.g.
HPACK encoding/decoding) as shown in #8882.

For sanity I did a final comparison of the "fast path" tweak using one
of the HPACK benchmarks:

(rawCnt & 1) == 0:

Benchmark                     (limitToAscii)  (sensitive)  (size)   Mode
Cnt      Score     Error  Units
HpackDecoderBenchmark.decode            true         true  MEDIUM  thrpt
30  50914.479 ± 940.114  ops/s


rawCnt == 2 || rawCnt == 4 || rawCnt == 6 || rawCnt == 8 ||  (rawCnt &
1) == 0:

Benchmark                     (limitToAscii)  (sensitive)  (size)   Mode
Cnt      Score      Error  Units
HpackDecoderBenchmark.decode            true         true  MEDIUM  thrpt
30  60036.425 ± 1478.196  ops/s
2019-02-28 20:41:16 +01:00
Dmitriy Dumanskiy
116f72db8d Legacy properties removed (#8839)
Motivation:

We can remove some properties for which we introduced replacements.

Modifications:

io.netty.buffer.bytebuf.checkAccessible, io.netty.leakDetectionLevel, org.jboss.netty.tryUnsafe properties removed

Result:

Code cleanup
2019-02-04 13:56:15 +01:00
田欧
e8efcd82a8 migrate java8: use requireNonNull (#8840)
Motivation:

We can just use Objects.requireNonNull(...) as a replacement for ObjectUtil.checkNotNull(....)

Modifications:

- Use Objects.requireNonNull(...)

Result:

Less code to maintain.
2019-02-04 10:32:25 +01:00
Nick Hill
0ac8db0307 CompositeByteBuf tidy-up (#8784)
Motivation

There's some miscellaneous cleanup/simplification of CompositeByteBuf
which would help make the code a bit clearer.

Modifications

- Simplify web of constructors and addComponents methods, reducing
duplication of logic
- Rename `Component.freeIfNecessary()` method to just `free()`, which is
less confusing (see #8641)
- Make loop in addComponents0(...) method more verbose/readable (see
https://github.com/netty/netty/pull/8437#discussion_r232124414)
- Simplify addition/subtraction in setBytes(...) methods

Result

Smaller/clearer code
2019-02-01 10:32:02 +01:00
田欧
d7648f1d93 use checkPositive/checkPositiveOrZero (#8803)
Motivation:

We have a utility method to check for > 0 and >0 arguments. We should use it.

Modification:

use checkPositive/checkPositiveOrZero instead of if statement.

Result:

Re-use utility method.
2019-01-31 09:06:59 +01:00
田欧
6222101924 migrate java8: use lambda and method reference (#8781)
Motivation:

We can use lambdas now as we use Java8.

Modification:

use lambda function for all package, #8751 only migrate transport package.

Result:

Code cleanup.
2019-01-29 14:06:05 +01:00
kezhenxu94
7b6336f1fd Java 8 Migration: remove uneccessary if statement (#8755)
Motivation:

As netty 4.x supported Java 6 we had various if statements to check for java versions < 8. We can remove these now.

Modification:

Remove unnecessary if statements that check for java versions < 8.

Result:

Cleanup code.
2019-01-25 08:57:11 +01:00
Nick Hill
9e7385ddba Fix three bugs in CompositeByteBuf (#8773)
Motivation

In #8758, @doom369 reported an infinite loop bug in CompositeByteBuf
which was introduced in #8437.

This is the same small fix for that, along with fixes for two other bugs
found while re-inspecting the changes and adding unit tests.

Modification

- Replace recursive call to toComponentIndex with toComponentIndex0 as
intended
- Add missed "lastAccessed" racy cache invalidation in capacity(int)
method
- Fix incorrect determination of initial offset in non-zero cIndex case
of updateComponentOffsets method
- New unit tests for previously uncovered methods

Results

Fewer bugs.
2019-01-24 14:59:33 +01:00
Dmitriy Dumanskiy
4a10357fd8 IDE warnings cleanup (#8768)
Motivation:

IDE shows some warnings

Modification:

Small IDE warnings cleanup in different places.

Result:

Less warnings
2019-01-23 14:01:48 +01:00
田欧
9d62deeb6f Java 8 migration: Use diamond operator (#8749)
Motivation:

We can use the diamond operator these days.

Modification:

Use diamond operator whenever possible.

Result:

More modern code and less boiler-plate.
2019-01-22 16:07:26 +01:00