Commit Graph

308 Commits

Author SHA1 Message Date
Norman Maurer
e542a2cf26
Use a non-volatile read for ensureAccessible() whenever possible to reduce overhead and allow better inlining. (#8266)
Motiviation:

At the moment whenever ensureAccessible() is called in our ByteBuf implementations (which is basically on each operation) we will do a volatile read. That per-se is not such a bad thing but the problem here is that it will also reduce the the optimizations that the compiler / jit can do. For example as these are volatile it can not eliminate multiple loads of it when inline the methods of ByteBuf which happens quite frequently because most of them a quite small and very hot. That is especially true for all the methods that act on primitives.

It gets even worse as people often call a lot of these after each other in the same method or even use method chaining here.

The idea of the change is basically just ue a non-volatile read for the ensureAccessible() check as its a best-effort implementation to detect acting on already released buffers anyway as even with a volatile read it could happen that the user will release it in another thread before we actual access the buffer after the reference check.

Modifications:

- Try to do a non-volatile read using sun.misc.Unsafe if we can use it.
- Add a benchmark

Result:

Big performance win when multiple ByteBuf methods are called from a method.

With the change:
UnsafeByteBufBenchmark.setGetLongUnsafeByteBuf  thrpt   20  281395842,128 ± 5050792,296  ops/s

Before the change:
UnsafeByteBufBenchmark.setGetLongUnsafeByteBuf  thrpt   20  217419832,801 ± 5080579,030  ops/s
2018-09-07 07:47:02 +02:00
Norman Maurer
052c2fbefe
Update to jmh 1.2.1 (#8270)
Motivation:

We should use the latest jmh version which also supports -prof dtraceasm on MacOS.

Modifications:

Update to latest jmh version.

Result:

Better benchmark / profiling support on MacOS.
2018-09-06 22:31:52 +02:00
Norman Maurer
02d559e6a4
Remove flags when running benchmarks. (#8262)
Motivation:

Some of the flags we used are not supported anymore on more recent JDK versions. We should just remove all of them and only keep what we really need. This may also reflect better what people use in production.

Modifications:

Remove some flags when running the benchmarks.

Result:

Benchmarks also run with JDK11.
2018-09-05 19:05:02 +02:00
Norman Maurer
8635d88d4d
Allow to generate a jmh uber jar to run benchmarks easily from cmdline with different arguments. (#8264)
Motivation:

It is sometimes useful to be able to run benchmarks easily from the commandline and passs different arguments / options here. We should support this.

Modifications:

Add the benchmark-jar profile which allows to generate such an "uber-jar" that can be used directly to run benchmarks as documented at http://openjdk.java.net/projects/code-tools/jmh/.

Result:

More flexible way to run benchmarks.
2018-09-05 18:28:35 +02:00
Carl Mastrangelo
379a56ca49 Add an Epoll benchmark
Motivation:
Optimizing the Epoll channel needs an objective measure of how fast
it is.

Modification:
Add a simple, closed loop,  ping-pong benchmark.

Result:
Benchmark can be used to measure #7816

Initial numbers:

```
Result "io.netty.microbench.channel.epoll.EpollSocketChannelBenchmark.pingPong":
  22614.403 ±(99.9%) 797.263 ops/s [Average]
  (min, avg, max) = (21093.160, 22614.403, 24977.387), stdev = 918.130
  CI (99.9%): [21817.140, 23411.666] (assumes normal distribution)

Benchmark                              Mode  Cnt      Score     Error  Units
EpollSocketChannelBenchmark.pingPong  thrpt   20  22614.403 ± 797.263  ops/s
```
2018-09-04 10:15:15 +02:00
Francesco Nigro
c78be33443 Added configurable ByteBuf bounds checking (#7521)
Motivation:

The JVM isn't always able to hoist out/reduce bounds checking (due to ref counting operations etc etc) hence making it configurable could improve performances for most CPU intensive use cases.

Modifications:

Each AbstractByteBuf bounds check has been tested against a new static final configuration property similar to checkAccessible ie io.netty.buffer.bytebuf.checkBounds.

Result:

Any user could disable ByteBuf bounds checking in order to get extra performances.
2018-09-03 20:33:47 +02:00
root
a580dc7585 [maven-release-plugin] prepare for next development iteration 2018-08-24 06:36:33 +00:00
root
3fc789e83f [maven-release-plugin] prepare release netty-4.1.29.Final 2018-08-24 06:36:06 +00:00
root
fcb19cb589 [maven-release-plugin] prepare for next development iteration 2018-07-27 04:59:28 +00:00
root
ff785fbe39 [maven-release-plugin] prepare release netty-4.1.28.Final 2018-07-27 04:59:06 +00:00
root
b4dbdc2036 [maven-release-plugin] prepare for next development iteration 2018-07-11 15:37:40 +00:00
root
1c16519ac8 [maven-release-plugin] prepare release netty-4.1.27.Final 2018-07-11 15:37:21 +00:00
root
7bb9e7eafe [maven-release-plugin] prepare for next development iteration 2018-07-10 05:21:24 +00:00
root
8ca5421bd2 [maven-release-plugin] prepare release netty-4.1.26.Final 2018-07-10 05:18:13 +00:00
Norman Maurer
83710cb2e1
Replace toArray(new T[size]) with toArray(new T[0]) to eliminate zero-out and allow the VM to optimize. (#8075)
Motivation:

Using toArray(new T[0]) is usually the faster aproach these days. We should use it.

See also https://shipilev.net/blog/2016/arrays-wisdom-ancients/#_conclusion.

Modifications:

Replace toArray(new T[size]) with toArray(new T[0]).

Result:

Faster code.
2018-06-29 07:56:04 +02:00
unknown
4a8d3a274c Including the setup code in the benchmark method to avoid JMH Invocation level hiccups.
Motivation:

The usage of Invocation level for JMH fixture methods (setup/teardown) inccurs in a significant overhead
in the benchmark time (see org.openjdk.jmh.annotations.Level documentation).

In the case of CodecInputListBenchmark, benchmarks are far too small (less than 50ns) and the Invocation
level setup offsets the measurement considerably.
On such cases, the recommended fix patch is to include the setup/teardown code in the benchmark method.

Modifications:

Include the setup/teardown code in the relevant benchmark methods.
Remove the setup/teardown methods from the benchmark class.

Result:

We run the entire benchmark 10 times with default parameters we observed:
- ArrayList benchmark affected directly by JMH overhead is now from 15-80% faster.
- CodecList benchmark is now 50% faster than original (even with the setup code being measured).
- Recyclable ArrayList is ~30% slower.
- All benchmarks have significant different means (ANOVA) and medians (Moore)

Mode: Throughput (Higher the better)

Method	              Full params		Factor	    Modified (Median)	Original (Median)
recyclableArrayList	 (elements = 1)		0.615520967	21719082.75	        35285691.2
recyclableArrayList	 (elements = 4)		0.699553431	17149442.76	        24514843.31
arrayList	         (elements = 4)		1.152666631	27120407.18	        23528404.88
codecOutList	     (elements = 1)		1.527275908	67251089.04	        44033359.47
codecOutList	     (elements = 4)		1.596917095	59174088.78	        37055204.03
arrayList	         (elements = 1)		1.878616889	62188238.24	        33103204.06

Environment:
Tests run on a Computational server with CPU: E5-1660-3.3GHZ  (6 cores + HT), 64 GB RAM.
2018-06-21 12:22:13 +02:00
unknown
cb420a9ffc Including the setup code in the benchmark method to avoid JMH Invocation level hiccups.
Motivation:

The usage of Invocation level for JMH fixture methods (setup/teardown) inccurs in a significant impact in
in the benchmark time (see org.openjdk.jmh.annotations.Level documentation).

When the benchmark and the setup/teardown is too small (less than a milisecond) the Invocation level might saturate the system with
timestamp requests and iteration synchronizations which introduce artificial latency, throughput, and scalability bottlenecks.

In the HeadersBenchmark, all benchmarks take less than 100ns and the Invocation level setup offsets the measurement considerably.
As fixture methods is defined for the entire class, this overhead also impacts every single benchmark in this class, not only
the ones that use the emptyHttpHeaders object (cleaned in the setup).

The recommended fix patch here is to include the setup/teardown code in the benchmark where the object is used.

Modifications:

Include the setup/teardown code in the relevant benchmark methods.
Remove the setup/teardown method of Invocation level from the benchmark class.

Result:

We run all benchmarks from HeadersBenchmark 10 times with default parameter, we observe:
- Benchmarks that were not directly affected by the fix patch, improved execution time.
    For instance, http2Remove with (exampleHeader = THREE) had its median reported as 2x faster than the original version.
- Benchmarks that had the setup code inserted (eg. http2AddAllFastest) did not suffer a significant punch in the execution time,
as the benchmarks are not dominated by the clear().

Environment:
Tests run on a Computational server with CPU: E5-1660-3.3GHZ  (6 cores + HT), 64 GB RAM.
2018-06-21 12:21:19 +02:00
Norman Maurer
64bb279f47 [maven-release-plugin] prepare for next development iteration 2018-05-14 11:11:45 +00:00
Norman Maurer
c67a3b0507 [maven-release-plugin] prepare release netty-4.1.25.Final 2018-05-14 11:11:24 +00:00
Norman Maurer
b75f44db9a [maven-release-plugin] prepare for next development iteration 2018-04-19 11:56:07 +00:00
Norman Maurer
04fac00c8c [maven-release-plugin] prepare release netty-4.1.24.Final 2018-04-19 11:55:47 +00:00
root
0a61f055f5 [maven-release-plugin] prepare for next development iteration 2018-04-04 10:44:46 +00:00
root
8c549bad38 [maven-release-plugin] prepare release netty-4.1.23.Final 2018-04-04 10:44:15 +00:00
Scott Mitchell
9d51a40df0 Update NetUtilBenchmark (#7826)
Motivation:
NetUtilBenchmark is using out of date data, throws an exception in the benchmark, and allocates a Set on each run.

Modifications:
- Update the benchmark and reduce each run's overhead

Result:
NetUtilBenchmark is updated.
2018-03-31 08:27:08 +02:00
Francesco Nigro
ed46c4ed00 Copies from read-only heap ByteBuffer to direct ByteBuf can avoid stealth ByteBuf allocation and additional copies
Motivation:

Read-only heap ByteBuffer doesn't expose array: the existent method to perform copies to direct ByteBuf involves the creation of a (maybe pooled) additional heap ByteBuf instance and copy

Modifications:

To avoid stressing the allocator with additional (and stealth) heap ByteBuf allocations is provided a method to perform copies using the (pooled) internal NIO buffer

Result:

Copies from read-only heap ByteBuffer to direct ByteBuf won't create any intermediate ByteBuf
2018-02-27 09:54:21 +09:00
Norman Maurer
69582c0b6c [maven-release-plugin] prepare for next development iteration 2018-02-21 12:52:33 +00:00
Norman Maurer
786f35c6c9 [maven-release-plugin] prepare release netty-4.1.22.Final 2018-02-21 12:52:19 +00:00
Norman Maurer
e71fa1e7b6 [maven-release-plugin] prepare for next development iteration 2018-02-05 12:02:35 +00:00
Norman Maurer
41ebb5fcca [maven-release-plugin] prepare release netty-4.1.21.Final 2018-02-05 12:02:19 +00:00
Julien Hoarau
3e6b54bb59 Fix failing h2spec tests 8.1.2.1 related to pseudo-headers validation
Motivation:

According to the spec:
All pseudo-header fields MUST appear in the header block before regular
header fields. Any request or response that contains a pseudo-header
field that appears in a header block after
a regular header field MUST be treated as malformed (Section 8.1.2.6).

Pseudo-header fields are only valid in the context in which they are defined.
Pseudo-header fields defined for requests MUST NOT appear in responses;
pseudo-header fields defined for responses MUST NOT appear in requests.
Pseudo-header fields MUST NOT appear in trailers.
Endpoints MUST treat a request or response that contains undefined or
invalid pseudo-header fields as malformed (Section 8.1.2.6).

Clients MUST NOT accept a malformed response. Note that these requirements
are intended to protect against several types of common attacks against HTTP;
they are deliberately strict because being permissive can expose
implementations to these vulnerabilities.

Modifications:

- Introduce validation in HPackDecoder

Result:

- Requests with unknown pseudo-field headers are rejected
- Requests with containing response specific pseudo-headers are rejected
- Requests where pseudo-header appear after regular header are rejected
- h2spec 8.1.2.1 pass
2018-01-29 19:42:56 -08:00
Norman Maurer
4c1e0f596a Use FastThreadLocal for CodecOutputList
Motivation:

We used Recycler for the CodecOutputList which is not optimized for the use-case of access only from the same Thread all the time.

Modifications:

- Use FastThreadLocal for CodecOutputList
- Add benchmark

Result:

Less overhead in our codecs.
2018-01-23 11:34:28 +01:00
Norman Maurer
ea58dc7ac7 [maven-release-plugin] prepare for next development iteration 2018-01-21 12:53:51 +00:00
Norman Maurer
96c7132dee [maven-release-plugin] prepare release netty-4.1.20.Final 2018-01-21 12:53:34 +00:00
Francesco Nigro
1cf2687244 Fixed JMH ByteBuf benchmark to avoid dead code elimination
Motivation:

The JMH doc suggests to use BlackHoles to avoid dead code elimination hence would be better to follow this best practice.

Modifications:

Each benchmark method is returning the ByteBuf/ByteBuffer to avoid the JVM to perform any dead code elimination.

Result:

The results are more reliable and comparable to the others provided by other ByteBuf benchmarks (eg HeapByteBufBenchmark)
2017-12-19 14:09:18 +01:00
Scott Mitchell
55ef09f191 Add HttpObjectEncoderBenchmark
Motivation:
Benchmark to measure HttpObjectEncoder performance.

Modifications:
- Create new benchmark HttpObjectEncoderBenchmark

Result:
JMH Microbenchmark for HttpObjectEncoder.
2017-12-16 13:47:34 +01:00
Scott Mitchell
5f0342ebe0 Add RedisEncoderBenchmark
Motivation:
Add a benchmark to measure RedisEncoder's performance

Modifications:
- Add RedisEncoderBenchmark

Result:
JMH benchmark exists to measure RedisEncoder's performance.
2017-12-16 13:42:50 +01:00
Norman Maurer
264a5daa41 [maven-release-plugin] prepare for next development iteration 2017-12-15 13:10:54 +00:00
Norman Maurer
0786c4c8d9 [maven-release-plugin] prepare release netty-4.1.19.Final 2017-12-15 13:09:30 +00:00
Norman Maurer
b2bc6407ab [maven-release-plugin] prepare for next development iteration 2017-12-08 09:26:15 +00:00
Norman Maurer
96732f47d8 [maven-release-plugin] prepare release netty-4.1.18.Final 2017-12-08 09:25:56 +00:00
Scott Mitchell
93b144b7b4 HttpMethod#valueOf improvement
Motivation:
HttpMethod#valueOf shows up on profiler results in the top set of
results. Since it is a relatively simple operation it can be improved in
isolation.

Modifications:
- Introduce a special case map which assigns each HttpMethod to a unique
index in an array and provides constant time lookup from a hash code
algorithm. When the bucket is matched we can then directly do equality
comparison instead of potentially following a linked structure when
HashMap has hash collisions.

Result:
~10% improvement in benchmark results for HttpMethod#valueOf

Benchmark                                     Mode  Cnt   Score   Error   Units
HttpMethodMapBenchmark.newMapKnownMethods    thrpt   16  31.831 ± 0.928  ops/us
HttpMethodMapBenchmark.newMapMixMethods      thrpt   16  25.568 ± 0.400  ops/us
HttpMethodMapBenchmark.newMapUnknownMethods  thrpt   16  51.413 ± 1.824  ops/us
HttpMethodMapBenchmark.oldMapKnownMethods    thrpt   16  29.226 ± 0.330  ops/us
HttpMethodMapBenchmark.oldMapMixMethods      thrpt   16  21.073 ± 0.247  ops/us
HttpMethodMapBenchmark.oldMapUnknownMethods  thrpt   16  49.081 ± 0.577  ops/us
2017-11-20 11:07:50 -08:00
Scott Mitchell
e6126215e0 DefaultHttp2FrameWriter reduce object allocation
Motivation:
DefaultHttp2FrameWriter#writeData allocates a DataFrameHeader for each write operation. DataFrameHeader maintains internal state and allocates multiple slices of a buffer which is a maximum of 30 bytes. This 30 byte buffer may not always be necessary and the additional slice operations can utilize retainedSlice to take advantage of pooled objects. We can also save computation and object allocations if there is no padding which is a common case in practice.

Modifications:
- Remove DataFrameHeader
- Add a fast path for padding == 0

Result:
Less object allocation in DefaultHttp2FrameWriter
2017-11-20 08:10:59 -08:00
Anuraag Agrawal
1f1a60ae7d Use Netty's DefaultPriorityQueue instead of JDK's PriorityQueue for scheduled tasks
Motivation:

`AbstractScheduledEventExecutor` uses a standard `java.util.PriorityQueue` to keep track of task deadlines. `ScheduledFuture.cancel` removes tasks from this `PriorityQueue`. Unfortunately, `PriorityQueue.remove` has `O(n)` performance since it must search for the item in the entire queue before removing it. This is fast when the future is at the front of the queue (e.g., already triggered) but not when it's randomly located in the queue.

Many servers will use `ScheduledFuture.cancel` on all requests, e.g., to manage a request timeout. As these cancellations will be happen in arbitrary order, when there are many scheduled futures, `PriorityQueue.remove` is a bottleneck and greatly hurts performance with many concurrent requests (>10K).

Modification:

Use netty's `DefaultPriorityQueue` for scheduling futures instead of the JDK. `DefaultPriorityQueue` is almost identical to the JDK version except it is able to remove futures without searching for them in the queue. This means `DefaultPriorityQueue.remove` has `O(log n)` performance.

Result:

Before - cancelling futures has varying performance, capped at `O(n)`
After - cancelling futures has stable performance, capped at `O(log n)`

Benchmark results

After - cancelling in order and in reverse order have similar performance within `O(log n)` bounds
```
Benchmark                                           (num)   Mode  Cnt       Score      Error  Units
ScheduledFutureTaskBenchmark.cancelInOrder            100  thrpt   20  137779.616 ± 7709.751  ops/s
ScheduledFutureTaskBenchmark.cancelInOrder           1000  thrpt   20   11049.448 ±  385.832  ops/s
ScheduledFutureTaskBenchmark.cancelInOrder          10000  thrpt   20     943.294 ±   12.391  ops/s
ScheduledFutureTaskBenchmark.cancelInOrder         100000  thrpt   20      64.210 ±    1.824  ops/s
ScheduledFutureTaskBenchmark.cancelInReverseOrder     100  thrpt   20  167531.096 ± 9187.865  ops/s
ScheduledFutureTaskBenchmark.cancelInReverseOrder    1000  thrpt   20   33019.786 ± 4737.770  ops/s
ScheduledFutureTaskBenchmark.cancelInReverseOrder   10000  thrpt   20    2976.955 ±  248.555  ops/s
ScheduledFutureTaskBenchmark.cancelInReverseOrder  100000  thrpt   20     362.654 ±   45.716  ops/s
```

Before - cancelling in order and in reverse order have significantly different performance at higher queue size, orders of magnitude worse than the new implementation.
```
Benchmark                                           (num)   Mode  Cnt       Score       Error  Units
ScheduledFutureTaskBenchmark.cancelInOrder            100  thrpt   20  139968.586 ± 12951.333  ops/s
ScheduledFutureTaskBenchmark.cancelInOrder           1000  thrpt   20   12274.420 ±   337.800  ops/s
ScheduledFutureTaskBenchmark.cancelInOrder          10000  thrpt   20     958.168 ±    15.350  ops/s
ScheduledFutureTaskBenchmark.cancelInOrder         100000  thrpt   20      53.381 ±    13.981  ops/s
ScheduledFutureTaskBenchmark.cancelInReverseOrder     100  thrpt   20  123918.829 ±  3642.517  ops/s
ScheduledFutureTaskBenchmark.cancelInReverseOrder    1000  thrpt   20    5099.810 ±   206.992  ops/s
ScheduledFutureTaskBenchmark.cancelInReverseOrder   10000  thrpt   20      72.335 ±     0.443  ops/s
ScheduledFutureTaskBenchmark.cancelInReverseOrder  100000  thrpt   20       0.743 ±     0.003  ops/s
```
2017-11-10 23:09:32 -08:00
Norman Maurer
188ea59c9d [maven-release-plugin] prepare for next development iteration 2017-11-08 22:36:53 +00:00
Norman Maurer
812354cf1f [maven-release-plugin] prepare release netty-4.1.17.Final 2017-11-08 22:36:33 +00:00
Carl Mastrangelo
83a19d5650 Optimistically update ref counts
Motivation:
Highly retained and released objects have contention on their ref
count.  Currently, the ref count is updated using compareAndSet
with care to make sure the count doesn't overflow, double free, or
revive the object.

Profiling has shown that a non trivial (~1%) of CPU time on gRPC
latency benchmarks is from the ref count updating.

Modification:
Rather than pessimistically assuming the ref count will be invalid,
optimistically update it assuming it will be.  If the update was
wrong, then use the slow path to revert the change and throw an
execption.  Most of the time, the ref counts are correct.

This changes from using compareAndSet to getAndAdd, which emits a
different CPU instruction on x86 (CMPXCHG to XADD).  Because the
CPU knows it will modifiy the memory, it can avoid contention.

On a highly contended machine, this can be about 2x faster.

There is a downside to the new approach.  The ref counters can
temporarily enter invalid states if over retained or over released.
The code does handle these overflow and underflow scenarios, but it
is possible that another concurrent access may push the failure to
a different location.  For example:

Time 1 Thread 1: obj.retain(INT_MAX - 1)
Time 2 Thread 1: obj.retain(2)
Time 2 Thread 2: obj.retain(1)

Previously Thread 2 would always succeed and Thread 1 would always
fail on the second access.  Now, thread 2 could fail while thread 1
is rolling back its change.

====

There are a few reasons why I think this is okay:

1. Buggy code is going to have bugs.  An exception _is_ going to be
   thrown.  This just causes the other threads to notice the state
   is messed up and stop early.
2. If high retention counts are a use case, then ref count should
   be a long rather than an int.
3. The critical section is greatly reduced compared to the previous
   version, so the likelihood of this happening is lower
4. On error, the code always rollsback the change atomically, so
   there is no possibility of corruption.

Result:
Faster refcounting

```
BEFORE:

Benchmark                                                                                             (delay)    Mode      Cnt         Score    Error  Units
AbstractReferenceCountedByteBufBenchmark.retainRelease_contended                                            1  sample  2901361       804.579 ±  1.835  ns/op
AbstractReferenceCountedByteBufBenchmark.retainRelease_contended                                           10  sample  3038729       785.376 ± 16.471  ns/op
AbstractReferenceCountedByteBufBenchmark.retainRelease_contended                                          100  sample  2899401       817.392 ±  6.668  ns/op
AbstractReferenceCountedByteBufBenchmark.retainRelease_contended                                         1000  sample  3650566      2077.700 ±  0.600  ns/op
AbstractReferenceCountedByteBufBenchmark.retainRelease_contended                                        10000  sample  3005467     19949.334 ±  4.243  ns/op
AbstractReferenceCountedByteBufBenchmark.retainRelease_uncontended                                          1  sample   456091        48.610 ±  1.162  ns/op
AbstractReferenceCountedByteBufBenchmark.retainRelease_uncontended                                         10  sample   732051        62.599 ±  0.815  ns/op
AbstractReferenceCountedByteBufBenchmark.retainRelease_uncontended                                        100  sample   778925       228.629 ±  1.205  ns/op
AbstractReferenceCountedByteBufBenchmark.retainRelease_uncontended                                       1000  sample   633682      2002.987 ±  2.856  ns/op
AbstractReferenceCountedByteBufBenchmark.retainRelease_uncontended                                      10000  sample   506442     19735.345 ± 12.312  ns/op

AFTER:
Benchmark                                                                                             (delay)    Mode      Cnt         Score    Error  Units
AbstractReferenceCountedByteBufBenchmark.retainRelease_contended                                            1  sample  3761980       383.436 ±  1.315  ns/op
AbstractReferenceCountedByteBufBenchmark.retainRelease_contended                                           10  sample  3667304       474.429 ±  1.101  ns/op
AbstractReferenceCountedByteBufBenchmark.retainRelease_contended                                          100  sample  3039374       479.267 ±  0.435  ns/op
AbstractReferenceCountedByteBufBenchmark.retainRelease_contended                                         1000  sample  3709210      2044.603 ±  0.989  ns/op
AbstractReferenceCountedByteBufBenchmark.retainRelease_contended                                        10000  sample  3011591     19904.227 ± 18.025  ns/op
AbstractReferenceCountedByteBufBenchmark.retainRelease_uncontended                                          1  sample   494975        52.269 ±  8.345  ns/op
AbstractReferenceCountedByteBufBenchmark.retainRelease_uncontended                                         10  sample   771094        62.290 ±  0.795  ns/op
AbstractReferenceCountedByteBufBenchmark.retainRelease_uncontended                                        100  sample   763230       235.044 ±  1.552  ns/op
AbstractReferenceCountedByteBufBenchmark.retainRelease_uncontended                                       1000  sample   634037      2006.578 ±  3.574  ns/op
AbstractReferenceCountedByteBufBenchmark.retainRelease_uncontended                                      10000  sample   506284     19742.605 ± 13.729  ns/op

```
2017-10-04 08:42:33 +02:00
Norman Maurer
625a7426cd [maven-release-plugin] prepare for next development iteration 2017-09-25 06:12:32 +02:00
Norman Maurer
f57d8f00e1 [maven-release-plugin] prepare release netty-4.1.16.Final 2017-09-25 06:12:16 +02:00
Norman Maurer
3c8c7fc7e9 Reduce performance overhead of ResourceLeakDetector
Motiviation:

The ResourceLeakDetector helps to detect and troubleshoot resource leaks and is often used even in production enviroments with a low level. Because of this its import that we try to keep the overhead as low as overhead. Most of the times no leak is detected (as all is correctly handled) so we should keep the overhead for this case as low as possible.

Modifications:

- Only call getStackTrace() if a leak is reported as it is a very expensive native call. Also handle the filtering and creating of the String in a lazy fashion
- Remove the need to mantain a Queue to store the last access records
- Add benchmark

Result:

Huge decrease of performance overhead.

Before the patch:

Benchmark                                           (recordTimes)   Mode  Cnt     Score     Error  Units
ResourceLeakDetectorRecordBenchmark.record                      8  thrpt   20  4358.367 ± 116.419  ops/s
ResourceLeakDetectorRecordBenchmark.record                     16  thrpt   20  2306.027 ±  55.044  ops/s
ResourceLeakDetectorRecordBenchmark.recordWithHint              8  thrpt   20  4220.979 ± 114.046  ops/s
ResourceLeakDetectorRecordBenchmark.recordWithHint             16  thrpt   20  2250.734 ±  55.352  ops/s

With this patch:

Benchmark                                           (recordTimes)   Mode  Cnt      Score      Error  Units
ResourceLeakDetectorRecordBenchmark.record                      8  thrpt   20  71398.957 ± 2695.925  ops/s
ResourceLeakDetectorRecordBenchmark.record                     16  thrpt   20  38643.963 ± 1446.694  ops/s
ResourceLeakDetectorRecordBenchmark.recordWithHint              8  thrpt   20  71677.882 ± 2923.622  ops/s
ResourceLeakDetectorRecordBenchmark.recordWithHint             16  thrpt   20  38660.176 ± 1467.732  ops/s
2017-09-18 16:36:19 -07:00
Norman Maurer
b967805f32 [maven-release-plugin] prepare for next development iteration 2017-08-24 15:38:22 +02:00