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Tue, 12 Jan 2021 00:27:24 +0000 Date: Mon, 11 Jan 2021 16:27:20 -0800 From: Roman Gushchin To: Jann Horn CC: Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Linux-MM , kernel list , Thomas Gleixner , Sebastian Andrzej Siewior , Johannes Weiner , Shakeel Butt , Suren Baghdasaryan , Minchan Kim Subject: Re: SLUB: percpu partial object count is highly inaccurate, causing some memory wastage and maybe also worse tail latencies? 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But since I > stumbled over this issue, I figured I should at least document/report > it, in case anyone is willing to pick it up.] Hi, Jann! Thank you very much for this report! It should be less of a problem since 5.9, but still on a machine with many CPUs a non-trivial amount of memory is wasted. I'll definitely take a look. Thanks!