Add some more metrics to the pooling allocator#11789
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alexcrichton merged 6 commits intobytecodealliance:mainfrom Oct 7, 2025
Merged
Add some more metrics to the pooling allocator#11789alexcrichton merged 6 commits intobytecodealliance:mainfrom
alexcrichton merged 6 commits intobytecodealliance:mainfrom
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This commit adds a few more metrics to the `PoolingAllocatorMetrics` type along the lines of accounting for more items as well as the unused slots in the pooling allocator. Notably the count of unused memory and table slots is exposed along with the number of bytes which are kept resident in these slots despite them not being in use. This involved a bit of plumbing to thread around the number of bytes that are actually kept resident to some more locations but is otherwise a pretty straightforward plumbing of accounting information we already had internally.
pchickey
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Oct 3, 2025
lann
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Oct 6, 2025
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| self.stripes | ||
| .iter() | ||
| .map(|i| i.allocator.unused_warm_slots()) | ||
| .sum() |
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I avoided this iteration + locking out of a (I guess probably irrational) fear of contention under heavy parallel load. Is that a pretty negligible concern here? If not, should we make a note about it in the pub method docs?
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I'll make a note yeah. My prediction is that it won't be too costly, but if it ends up causing problems we can probably work around it with atomic counters.
prtest:full
bongjunj
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Oct 20, 2025
* Add some more metrics to the pooling allocator This commit adds a few more metrics to the `PoolingAllocatorMetrics` type along the lines of accounting for more items as well as the unused slots in the pooling allocator. Notably the count of unused memory and table slots is exposed along with the number of bytes which are kept resident in these slots despite them not being in use. This involved a bit of plumbing to thread around the number of bytes that are actually kept resident to some more locations but is otherwise a pretty straightforward plumbing of accounting information we already had internally. * Fix configured build * Add some docs * Only run new test on Linux * Try to fix ASAN prtest:full * Shrink pooling size in tests
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This commit adds a few more metrics to the
PoolingAllocatorMetricstype along the lines of accounting for more items as well as the unused slots in the pooling allocator. Notably the count of unused memory and table slots is exposed along with the number of bytes which are kept resident in these slots despite them not being in use. This involved a bit of plumbing to thread around the number of bytes that are actually kept resident to some more locations but is otherwise a pretty straightforward plumbing of accounting information we already had internally.