lkml.org 
[lkml]   [2002]   [May]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] 2.5.14 IDE 56
Date
From
> You are right on the money!
> There is about 35-40% throughput killjoy "copy-from-kernel-to-userspace".
> It is easy to demo if you have a bus analizer and can do accounting on the
> data io less the command block overhead.
>
> CR3's are your friend, not ...

You should be able to verify that by using large O_DIRECT I/O's. The
block layer itself may well be part of the overhead. With the scsi layer,
the block->scsi handling code is definitely a bottleneck to performance
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:25    [W:0.110 / U:0.396 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site