Use Two way algorithm to optimize ByteBufUtil.indexOf() method
Motivation:
ByteBufUtil.indexOf can be inefficient for substring search on
ByteBuf, in terms of algorithm complexity (O(needle.readableBytes * haystack.readableBytes)), consider using the Two Way algorithm to optimize the ByteBufUtil.indexOf() method
Modification:
Use the Two Way algorithm to optimize ByteBufUtil.indexOf() method.
Result:
The performance of the ByteBufUtil.indexOf() method is higher than the original implementation
Motivation:
b89a807d15 moved the buffer tests to junit5 but introduced a small error which could lead to test-failure
Modifications:
Correctly override the method and assert that super throws (as we can not expand the buffer).
Result:
No more test failures
Motivation:
JUnit 5 is more expressive, extensible, and composable in many ways, and it's better able to run tests in parallel.
Modifications:
Use JUnit5 in tests
Result:
Related to https://github.com/netty/netty/issues/10757
Motivation:
When object-references are both same, the method should return 0 directly with no necessary go loop&compare the content of the ByteBuf.
Modification:
Added short circuit when both object-references are the same for equals and compare methods.
Result:
Added short circuit code.
Motivation:
NullChecks resulting in a NullPointerException or IllegalArgumentException, numeric ranges (>0, >=0) checks, not empty strings/arrays checks must never be anonymous but with the parameter or variable name which is checked. They must be specific and should not be done with an "OR-Logic" (if a == null || b == null) throw new NullPointerEx.
Modifications:
* import static relevant checks
* Replace manual checks with ObjectUtil methods
Result:
All checks needed are done with ObjectUtil, some exception texts are improved.
Fixes#11170
Motivation:
Switch statements should always have a default block to ensure we not "fall-through" by mistake.
Modification:
Add default block
Result:
code cleanup.
Signed-off-by: xingrufei <xingrufei@sogou-inc.com>
Co-authored-by: xingrufei <xingrufei@sogou-inc.com>
Motivation:
Alignment handling was broken, and basically turned into a fixed offset into each allocation address regardless of its initial value, instead of ensuring that the allocated address is either aligned or bumped to the nearest alignment offset.
The brokenness of the alignment handling extended so far, that overlapping ByteBuf instances could even be created, as was seen in #11101.
Modification:
Instead of fixing the per-allocation pointer bump, we now ensure that 1) the minimum page size is a whole multiple of the alignment, and 2) the reference memory for each chunk is bumped to the nearest aligned address, and finally 3) ensured that the reservations are whole multiples of the alignment, thus ensuring that the next allocation automatically occurs from an aligned address.
Incidentally, (3) above comes for free because the reservations are in whole pages, and in (1) we ensured that pages are sized in whole multiples of the alignment.
In order to ensure that the memory for a chunk is aligned, we introduce some new PlatformDependent infrastructure.
The PlatformDependent.alignDirectBuffer will produce a slice of the given buffer, and the slice will have an address that is aligned.
This method is plainly available on ByteBuffer in Java 9 onwards, but for pre-9 we have to use Unsafe, which means it can fail and might not be available on all platforms.
Attempts to create a PooledByteBufAllocator that uses alignment, when this is not supported, will throw an exception.
Luckily, I think use of aligned allocations are rare.
Result:
Aligned pooled byte bufs now work correctly, and never have any overlap.
Fixes#11101
Motivation:
Components in a composite buffer can "go missing" if the composite is a slice of another composite and the parent has changed its layout.
Modification:
Where we would previously have thrown a NullPointerException, we now have a null-check for the component, and we instead throw an IllegalStateException with a more descriptive message.
Result:
It's now a bit easier to understand what is going on in these situations.
Fixes#10908
Motivation:
File.createTempFile(String, String)` will create a temporary file in the system temporary directory if the 'java.io.tmpdir'. The permissions on that file utilize the umask. In a majority of cases, this means that the file that java creates has the permissions: `-rw-r--r--`, thus, any other local user on that system can read the contents of that file.
This can be a security concern if any sensitive data is stored in this file.
This was reported by Jonathan Leitschuh <jonathan.leitschuh@gmail.com> as a security problem.
Modifications:
Use Files.createTempFile(...) which will use safe-defaults when running on java 7 and later. If running on java 6 there isnt much we can do, which is fair enough as java 6 shouldnt be considered "safe" anyway.
Result:
Create temporary files with sane permissions by default.
Motivation:
when customer need large of 'byteBuf.capacity' in [7168, 8192], the size of 'chunk.subpages' may be inflated when large of byteBuf be released, not consistent with other 'byteBuf.capacity'
Modification:
when maxNumElems == 1 need consider remove from pool
Result:
Fixes#10896.
Co-authored-by: zxingy <zxingy@servyou.com.cn>
Motivation:
Found an invalid comment in UnpooledDirectByteBuf.
Modification:
Fixed a comment in UnpooledDirectByteBuf.
Result:
Fixed a comment in UnpooledDirectByteBuf.
Motivation:
We rely on this functionality in PoolChunk, and a bug was caught by a non-deterministic test failure
Modification:
Went back to the Algorithms book, and reimplemented remove() the way it was meant to.
Result:
No test failures after 200.000 runs, so we have some confidence the code is correct now.
Motivation:
The uncached access to PoolChunk can be made faster, and avoid allocating boxed Longs, if we have a primitive hash map and priority queue implementation for it.
Modification:
Add bespoke primitive implementations of a hash map and a priority queue for PoolChunk.
Remove all the long-boxing caused by the previous implementation.
The hashmap is a linear probing map with a fairly short probe that keeps the search within a couple of cache lines.
The priority queue is the same binary heap algorithm that's described in Algorithms by Sedgewick and Wayne.
The implementation avoids the Long boxing by relying on a long[] array.
This makes the internal-remove method faster, which is an important operation in PoolChunk.
Result:
Roughly 13% performance uplift in buffer allocations that miss cache.
Motivation:
https://github.com/netty/netty/pull/10267 introduced a change that reduced the fragmentation. Unfortunally it also introduced a regression when it comes to caching of normal allocations. This can have a negative performance impact depending on the allocation sizes.
Modifications:
- Fix algorithm to calculate the array size for normal allocation caches
- Correctly calculate indeox for normal caches
- Add unit test
Result:
Fixes https://github.com/netty/netty/issues/10805
Motivation:
Passing a null value of byte[] to the `Unsafe.copyMemory(xxx)` would cause the JVM crash
Modification:
Add null checking before calling `PlatformDependent.copyMemory(src, xxx)`
Result:
Fixes#10791 .
