lkml.org 
[lkml]   [1996]   [Oct]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectMemory upgrade: not faster / nfs
From
Date
Problem:
! NFS is a filesystem. Filesystems are not cached.
! The only thing that's cached in UN*X are block
! devices. This is the wrong place to cache.


My fastest CPU is a Pentium 100 on a diskless client.
I thought that I get only 5% cpu usage because I am
swapping over NFS. I bought another 32MB but the CPU
usage did not increase :-( The Ethernet LED is still
busy all the time.
I tracked the problem down to the following problem:

! NFS is a filesystem. Filesystems are not cached.
! The only thing that's cached in UN*X are block
! devices.

Because of this configuration the caching is done
in the server, not on the client =:-O
Transmitting data over the network is some magnitudes
slower than reading it from the buffers.
Compiling is a very I/O intensive task (all the
include files, the compiler, the .I .S .o files).
For this it doesn't matter how much memory I have on
my client. I can't get more than 5% CPU usage when
compiling.

Questions:
Is it correct how I see these things?
Why are filesystems not buffered?
Is there a nfs implementation that does buffering?


Christoph Trautwein email trautw@fzi.de
click <A HREF="http://www.fzi.de/sim/people/trautw/index.html">here </A>
FZI Forschungszentrum Informatik phone +49-721-9654-414
FZI,Haid-und-Neu-Str. 10-14, 76131 Karlsruhe, Germany fax +49-721-9654-474
X400: C=de; A=d400-gw; P=fzi; S=trautw
* PLEASE USE PGP TO ENCRYPT EMAILS! Please use MIME formatted EMails. *
\
 
 \ /
  Last update: 2005-03-22 13:37    [W:0.185 / U:0.028 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site