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

[Pekka Enberg]

Hi,

On 01/02/2019 4.34, Christopher Lameter wrote:
> On Fri, 1 Feb 2019, 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.
>
> Hmm.. I wonder if there are any tools that depend on the field width here?

It's possible, but it's more likely that userspace parses by whitespace 
because it's easier to write it that way.

At least procps, which is used by slabtop, is prepared to parse a cache 
name of 128 characters. See the scanf() call in parse_slabinfo20() 
function in proc/slab.c of procps:

  http://procps.sourceforge.net/

Of course, testing with slabtop would make sense.

- Pekka