lkml.org 
[lkml]   [2002]   [Apr]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH] zerocopy NFS updated
From
Hi, 

jakob> Won't this serialize too much ? I mean, consider the situation where we
jakob> have file-A and file-B completely in cache, while file-C needs to be
jakob> read from the physical disk.
jakob>
jakob> Three different clients (A, B and C) request file-A, file-B and file-C
jakob> respectively. The send of file-C is started first, and the sends of files
jakob> A and B (which could commence immediately and complete at near wire-speed)
jakob> will now have to wait (leaving the NIC idle) until file-C is read from
jakob> the disks.
jakob>
jakob> Even if it's not the entire file but only a single NFS request (probably 8kB),
jakob> one disk seek (7ms) is still around 85 kB, or 10 8kB NFS requests (at 100Mbit).
jakob>
jakob> Or am I misunderstanding ? Will your UDP sendpage() queue the requests ?

No problem.
On my implementation, at the beginning a knfsd grabs all pages -- a part
of file-C -- to reply to the NFS client. After that the knfsd starts to
send them. It won't block any other knfsds during disk I/Os.

Thank you,
Hirokazu Takahashi.

-
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 13:22    [W:1.116 / U:0.016 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site