Re: Drastic Slowdown of 'fseek()' Calls From 2.4 to 2.6 -- VMM Change?

[Bill Davidsen]

Hans Reiser wrote:
> Andrew Morton wrote:
>
> > runs like a dog on 2.6's reiserfs.  libc is doing a (probably) 128k read
> > on every fseek.
> >
> > - There may be a libc stdio function which allows you to tune this
> >  behaviour.
> >
> > - libc should probably be a bit more defensive about this anyway -
> >  plainly the filesystem is being silly.
> >  
> I really thank you for isolating the problem, but I don't see how you
> can do other than blame glibc for this.  The recommended IO size is only
> relevant to uncached data, and glibc is using it regardless of whether
> or not it is cached or uncached.   Do I misunderstand something myself here?

I think the issue is not "blame" but what effect this behavior would 
have on things like database loads, where seek-write would be common. 
Good to get this info to users and admins.

--
   -bill davidsen (davidsen@xxxxxxx)
"The secret to procrastination is to put things off until the
 last possible moment - but no longer"  -me

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