From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj@kernel.org>
Subject: Re: [PATCH 00/40] Memory allocation profiling
Date: Wed, 3 May 2023 08:24:05 -1000
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Sender: Tejun Heo <htejun@gmail.com>
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To: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Michal Hocko <mhocko@suse.com>, Suren Baghdasaryan <surenb@google.com>, akpm@linux-foundation.org, vbabka@suse.cz, hannes@cmpxchg.org, roman.gushchin@linux.dev, mgorman@suse.de, dave@stgolabs.net, willy@infradead.org, liam.howlett@oracle.com, corbet@lwn.net, void@manifault.com, peterz@infradead.org, juri.lelli@redhat.com, ldufour@linux.ibm.com, catalin.marinas@arm.com, will@kernel.org, arnd@arndb.de, tglx@linutronix.de, mingo@redhat.com, dave.hansen@linux.intel.com, x86@kernel.org, peterx@redhat.com, david@redhat.com, axboe@kernel.dk, mcgrof@kernel.org, masahiroy@kernel.org, nathan@kernel.org, dennis@kernel.org, muchun.song@linux.dev, rppt@kernel.org, paulmck@kernel.org, pasha.tatashin@soleen.com, yosryahmed@google.com, yuzhao@google.com, dhowells@redhat.com, hughd@google.com

Hello,

On Wed, May 03, 2023 at 01:51:23PM -0400, Kent Overstreet wrote:
> Do you have example output?

Not right now. It's from many months ago. It's just a script I could find
easily.

> TBH I'm skeptical that it's even possible to do full memory allocation
> profiling with tracing/bpf, due to recursive memory allocations and
> needing an index of outstanding allcations.

There are some issues e.g. w/ lossy updates which should be fixed from BPF
side but we do run BPF on every single packet and IO on most of our
machines, so basing this argument on whether tracking all memory allocations
from BPF is possible is probably not a winning strategy for this proposal.

Thanks.

-- 
tejun