lkml.org 
[lkml]   [2008]   [May]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [patch 00/41] cpu alloc / cpu ops v3: Optimize per cpu access
On Thu, 29 May 2008, Andrew Morton wrote:

> ext3 maintains three percpu_counters per mount. Each percpu_counter
> does one percpu_alloc. People can mount an arbitrary number of ext3
> filesystems!

But its 4 bytes per alloc right?

> Another: there are two percpu_counters (and hence two percpu_alloc()s)
> per backing_dev_info. One backing_dev_info per disk and people have
> been known to have thousands (iirc ~10,000) disks online.

8 bytes per backing device. 80000 bytes for 10000 disks.
> And those examples were plucked only from today's kernel. Who knows
> what other problems will be in 2.6.45?

We can always increase the sizes.



\
 
 \ /
  Last update: 2008-05-30 08:25    [from the cache]
©2003-2011 Jasper Spaans