[lkml]   [2004]   [Jan]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: 2.6.1-rc1-tiny2
På on , 07/01/2004 klokka 15:10, skreiv Matt Mackall:
> NFS is a good example of why the guarantees of mempool are being
> overstated - it still needs to allocate SKBs to make progress and
> preallocating a pool for other data structures can make that fail
> where it otherwise might not. The pool size for NFS (32) is also
> completely arbitrary as far as I can tell.

If you are in a hardware situation where you actually care about the
permanent size of that mempool, then you're barking up entirely the
wrong tree: there is a hell of a lot more memory to reclaim from not
having to build up all those nfs_page lists in the first place.

i.e. Rip out the entire asynchronous NFS read/write support, not just
the mempools.

As for the usefulness of the mempools in the situation where you have
asynchronous I/O: I agree that the socket layer screws any chance of a
guarantee. So does the server if it goes down, the network itself can
screw you,.... All in all, it is surprising how few guarantees NFS
offers you.
I therefore see the mempools as more of an optimization that mainly
avoid sleeping under a certain limited set of "reasonable"

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:59    [W:0.049 / U:10.500 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site