Re: [PATCH] mm/slab: Increase width of first /proc/slabinfo column

Andrew Morton
2019-02-01T22:03:50Z

On Thu, 31 Jan 2019 18:43:10 -0800 Matthew Wilcox <willy@infradead.org> wrote:

> On Fri, Feb 01, 2019 at 11:42:42AM +1100, Tobin C. Harding wrote:
> > Currently when displaying /proc/slabinfo if any cache names are too long
> > then the output columns are not aligned. We could do something fancy to
> > get the maximum length of any cache name in the system or we could just
> > increase the hardcoded width. Currently it is 17 characters. Monitors
> > are wide these days so lets just increase it to 30 characters.
>
> I had a proposal some time ago to turn the slab name from being kmalloced
> to being an inline 16 bytes (with some fun hacks for cgroups). I think
> that's a better approach than permitting such long names. For example,
> ext4_allocation_context could be shortened to ext4_alloc_ctx without
> losing any expressivity.
>

There are some back-compatibility concerns here. And truncating long
names might result in duplicates.