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* scsi_malloc fragmentation in 2.4.X
@ 2002-12-20 20:31 Justin T. Gibbs
  2002-12-20 20:36 ` Christoph Hellwig
  2002-12-20 20:39 ` Doug Ledford
  0 siblings, 2 replies; 3+ messages in thread
From: Justin T. Gibbs @ 2002-12-20 20:31 UTC (permalink / raw)
  To: linux-scsi

Are there any plans to correct the scsi_malloc fragmentation problems
in 2.4.X?  It looks like this problem has been addressed in 2.5.X by using
memory pools, but the current 2.4.X solution of just "backing off a bit"
if scsi_malloc returns NULL, is much less than ideal.  At least the user
isn't assaulted by lots of "Running really short on DMA buffers" messages,
but performance does suffer when the only reason you can't queue an I/O
is that the pre-allocated S/G list memory is so poorly managed that the
available memory can't be used.

--
Justin


^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: scsi_malloc fragmentation in 2.4.X
  2002-12-20 20:31 scsi_malloc fragmentation in 2.4.X Justin T. Gibbs
@ 2002-12-20 20:36 ` Christoph Hellwig
  2002-12-20 20:39 ` Doug Ledford
  1 sibling, 0 replies; 3+ messages in thread
From: Christoph Hellwig @ 2002-12-20 20:36 UTC (permalink / raw)
  To: Justin T. Gibbs; +Cc: linux-scsi

On Fri, Dec 20, 2002 at 01:31:58PM -0700, Justin T. Gibbs wrote:
> Are there any plans to correct the scsi_malloc fragmentation problems
> in 2.4.X?

Someone from Veritas had a patch for this, but unfortunately it seems
that one got left somewhere.


^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: scsi_malloc fragmentation in 2.4.X
  2002-12-20 20:31 scsi_malloc fragmentation in 2.4.X Justin T. Gibbs
  2002-12-20 20:36 ` Christoph Hellwig
@ 2002-12-20 20:39 ` Doug Ledford
  1 sibling, 0 replies; 3+ messages in thread
From: Doug Ledford @ 2002-12-20 20:39 UTC (permalink / raw)
  To: Justin T. Gibbs; +Cc: linux-scsi

On Fri, Dec 20, 2002 at 01:31:58PM -0700, Justin T. Gibbs wrote:
> Are there any plans to correct the scsi_malloc fragmentation problems
> in 2.4.X?  It looks like this problem has been addressed in 2.5.X by using
> memory pools, but the current 2.4.X solution of just "backing off a bit"

Not in my plans anyway.  There's so much broken in 2.4 that fixing it 
means upgrading to 2.6 when available IMHO, so that's why I'm trying to 
get 2.6 fixed up as fast as possible and letting 2.4 be as it is.


-- 
  Doug Ledford <dledford@redhat.com>     919-754-3700 x44233
         Red Hat, Inc. 
         1801 Varsity Dr.
         Raleigh, NC 27606
  

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2002-12-20 20:39 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2002-12-20 20:31 scsi_malloc fragmentation in 2.4.X Justin T. Gibbs
2002-12-20 20:36 ` Christoph Hellwig
2002-12-20 20:39 ` Doug Ledford

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