it's much less expensive to just calculate the modulo of the current tick and 20, and overwrite past entries. The effect is the same. The only difference is that the arrays won't be ordered by time, but that doesn't matter anyway.
This is better for performance because these then don't need to be reevaluated every time they are called.
When encountering an unqualified function or constant reference, PHP will first try to locate a symbol in the current namespace by that name, and then fall back to the global namespace.
This short-circuits the check, which has substantial performance effects in some cases - in particular, ord(), chr() and strlen() show ~1500x faster calls when they are fully qualified.
However, this doesn't mean that PM is getting a massive amount faster. In real world terms, this translates to about 10-15% performance improvement.
But before anyone gets excited, you should know that the CodeOptimizer in the PreProcessor repo has been applying fully-qualified symbol optimizations to Jenkins builds for years, which is one of the reasons why Jenkins builds have better performance than home-built or source installations.
We're choosing to do this for the sake of future SafePHP integration and also to be able to get rid of the buggy CodeOptimizer, so that phar and source are more consistent.
@shoghicp, y u do dis... I almost created a sub-packet architecture to deal with this shit :(
This mess really ought to be split into multiple packets. Perhaps the PacketPool can be extended to do that in the future.
valid crashdumps are usually self explanatory and include all required information like OS/version/etc, so there's no need to force reporters to rewrite a bunch of extra information that should already be in the crashdump.
Since 3.2 there have been some runtime performance issues related to garbage collection and dynamic AsyncWorker booting. This is partly because of GC being dumb about shutting down what it thinks are "unused" workers. A worker which has been idle for a single tick is considered the same as a worker which has been idle for hours. The result of this is that on active servers, workers would get shut down and then immediately restarted because of something like chunk sending. Since booting an async worker is frightfully expensive, this causes lag spikes, which is obviously bad.
This commit changes the GC mechanism to only shutdown workers which have not been used for the last 5 minutes.
