Am 2024-05-08 18:45, schrieb Bojan Novković:
Hi,On 5/7/24 14:02, Alexander Leidinger wrote:Hi, I created some graphs of the memory fragmentation. https://www.leidinger.net/blog/2024/05/07/plotting-the-freebsd-memory-fragmentation/My goal was not comparing a specific change on a given benchmark, but to "have something which visualizes memory fragmentation". As part of that, Bojans commit https://cgit.freebsd.org/src/commit/?id=7a79d066976149349ecb90240d02eed0c4268737 was just in the middle of my data collection. I have the impression that it made a positive difference in my non deterministic workload.Thank you for working on this, the plots look great! They provide a really clean visual overview of what's happening.I'm working on another type of memory visualization which might interest you, I'll share it with you once its done. One small nit - the fragmentation index does not quantify fragmentation for UMA buckets, but for page allocator freelists.
Do I get it more correctly now: UMA buckets are type/structure specific allocation lists, and the page allocator freelists are size-specific allocation lists (which are used by UMA when no free item is available in a bucket)?
Is there anything which prevents https://reviews.freebsd.org/D40575 to be committed?D40575 is closely tied to the compaction patch (D40772) which is currently on hold until another issue is solved (see D45046 and related revisions for more details).
Any idea about https://reviews.freebsd.org/D16620 ? Is D45046 supposed to replace this, or is it about something else? I wanted to try D16620, but it doesn't apply and my naive/mechanical way of applying it panics.
I didn't consider landing D40575 because of that, but I guess it could be useful on its own.
It at least gives a way to quantify with numbers resp. qualitatively visualize. And as such it may help in visualizing differences like with your guard-pages commit. I wonder if the segregation of nofree allocations may result in a similar improvement for long-running systems.
Bye, Alexander. -- http://www.Leidinger.net alexan...@leidinger.net: PGP 0x8F31830F9F2772BF http://www.FreeBSD.org netch...@freebsd.org : PGP 0x8F31830F9F2772BF
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