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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Hyeonggon Yoo' <42.hyeyoo@gmail.com>,
        Vlastimil Babka <vbabka@suse.cz>
CC:     Christoph Lameter <cl@gentwo.org>,
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        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: RE: Do we really need SLOB nowdays?
Thread-Topic: Do we really need SLOB nowdays?
Thread-Index: AQHYJLAyvH6iV8tqykeD7oCpMSL3UayZeSGA
Date:   Fri, 18 Feb 2022 16:10:28 +0000
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From: Hyeonggon Yoo
> Sent: 18 February 2022 10:13
...
> I think SLUB can be memory-efficient as SLOB.
> Is SLOB (Address-Ordered next^Wfirst fit) stronger to fragmentation than SLUB?

Dunno, but I had to patch the vxworks malloc to use 'best fit'
because 'first fit' based on a fifo free list was really horrid.

I can't imagine an address ordered 'first fit' really being that much better.

There are probably a lot more allocs and frees than the kernel used to have.

Also isn't the performance of a 'first fit' going to get horrid
when there are a lot of small items on the free list.

Does SLUB split pages into 3s and 5s (on cache lime boundaries)
as well as powers of 2?

	David

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