Re: [PATCH v2 2/2] SLUB: Mark merged slab caches in /proc/slabinfo

Linus Torvalds
2010-09-14T20:06:29Z

On Tue, Sep 14, 2010 at 1:00 PM, David Rientjes <rientjes@google.com> wrote:
>
> I can understand how it's confusing that only the first slab cache name is
> being emitted, and I think that can be changed, but this shows way too
> much information that is already available when CONFIG_SLUB_DEBUG is used
> via the sysfs interface.

Umm. Not in any readable form, it isn't.

The cause for this is that I made a bug-report about the wrong slab
info, with me claiming 400+ thousand entries (taking up 10M of memory)
for a slub cache that turned out to be entirely innocent.

That's what /proc/slabinfo said, and quite frankly, /proc/slabinfo was
simply _lying_. It gave very misleading output.

In my not-so-humble opinion, either the merging needs to go away
entirely, or the misleading output needs to be fixed. The whole (and
_only_) reason for /proc/slabinfo is to show where memory is being
used, so if that file is misleading, then it's worse than useless.
Pointing to some other /sys file as having more information doesn't
change that in the least.

Linus