Re: + mm-slab-shorten-kmalloc-cache-names-for-large-sizes.patch added to -mm tree

From: Matthew Wilcox
Date: Sat Sep 08 2018 - 11:59:22 EST


On Sat, Sep 08, 2018 at 10:03:06AM -0400, Johannes Weiner wrote:
> On Fri, Sep 07, 2018 at 10:58:16PM +0300, Alexey Dobriyan wrote:
> > On Thu, Sep 06, 2018 at 03:48:49PM -0700, akpm@xxxxxxxxxxxxxxxxxxxx wrote:
> > > - {"kmalloc-1024", 1024}, {"kmalloc-2048", 2048},
> > > - {"kmalloc-4096", 4096}, {"kmalloc-8192", 8192},
> > > - {"kmalloc-16384", 16384}, {"kmalloc-32768", 32768},
> > > - {"kmalloc-65536", 65536}, {"kmalloc-131072", 131072},
> > > - {"kmalloc-262144", 262144}, {"kmalloc-524288", 524288},
> > > - {"kmalloc-1048576", 1048576}, {"kmalloc-2097152", 2097152},
> > > - {"kmalloc-4194304", 4194304}, {"kmalloc-8388608", 8388608},
> > > - {"kmalloc-16777216", 16777216}, {"kmalloc-33554432", 33554432},
> > > - {"kmalloc-67108864", 67108864}
> > > + {"kmalloc-1k", 1024}, {"kmalloc-2k", 2048},
> > > + {"kmalloc-4k", 4096}, {"kmalloc-8k", 8192},
> > > + {"kmalloc-16k", 16384}, {"kmalloc-32k", 32768},
> > > + {"kmalloc-64k", 65536}, {"kmalloc-128k", 131072},
> > > + {"kmalloc-256k", 262144}, {"kmalloc-512k", 524288},
> > > + {"kmalloc-1M", 1048576}, {"kmalloc-2M", 2097152},
> > > + {"kmalloc-4M", 4194304}, {"kmalloc-8M", 8388608},
> > > + {"kmalloc-16M", 16777216}, {"kmalloc-32M", 33554432},
> > > + {"kmalloc-64M", 67108864}
> >
> > I'd rather use KB and MB suffixes or at least capital 'K'.
>
> I like k and M better.

k and M work for me too. It we were going to be anal then we should
go with the IEC standard of KiB and MiB, but we're trying to make
/proc/slabinfo a little less ugly, and so we have 16 characters to work
with. "dma-kmalloc-256KiB" is 18 characters. The obvious place to lose
two characters is the "iB" which are implicit; we know we're measuring
bytes and the binary nature is assumed in this context of memory bytes
(not storage bytes). "dma-kmalloc-256k" is better.