All of lore.kernel.org
 help / color / mirror / Atom feed
From: Jordi Prats <jprats@cesca.es>
To: chuck.lever@ORACLE.COM, Thomas.Talpey@netapp.com
Cc: nfs@lists.sourceforge.net
Subject: Re: reply cache
Date: Mon, 15 Oct 2007 20:28:32 +0200	[thread overview]
Message-ID: <4713B150.2050607@cesca.es> (raw)
In-Reply-To: <47139BEC.8030400@oracle.com>

Thank you!

I miss understood the reply cache, I was thinking it as a way it caches 
the answer to a question like "which are the attributes of that file?"

Now I'm happy with my zero hits ;)

Jordi

Chuck Lever wrote:
> Jordi Prats wrote:
>> According to the file fs/nfsd/nfscache.c (line 30 on 2.6.23), reply 
>> cache is fixed size. Why is this a fixed size cache? Shouldn't be 
>> relative to the number of nfsd threads? I've a server with this 
>> statistics:
>>
>> rc 0 959398 336415498
>>
>> By what I've been researching this means: 0 hits, 959398 misses (I 
>> supose that means something like "recently deleted") and 336415498 not 
>> in cache (and never has been). Is that right?
> 
> A DRC hit implies the client is retransmitting.  Not having any hits is 
> a good thing -- it means your server is able to handle all your clients 
> without much sweat.
> 
>> Modifying the CACHESIZE to a bigger size do you think it could enhance 
>> NFS performance by getting some hits on the reply cache?
> 
> The server's DRC is not a performance feature.  It's a way for the 
> server to detect replayed requests from the client.  In a perfect world, 
> servers wouldn't even have one.

-------------------------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc.
Still grepping through log files to find problems?  Stop.
Now Search log events and configuration files using AJAX and a browser.
Download your FREE copy of Splunk now >> http://get.splunk.com/
_______________________________________________
NFS maillist  -  NFS@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/nfs

  reply	other threads:[~2007-10-15 18:21 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-10-15 16:53 reply cache Jordi Prats
2007-10-15 16:57 ` Chuck Lever
2007-10-15 18:28   ` Jordi Prats [this message]
2007-10-15 17:09 ` Talpey, Thomas

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4713B150.2050607@cesca.es \
    --to=jprats@cesca.es \
    --cc=Thomas.Talpey@netapp.com \
    --cc=chuck.lever@ORACLE.COM \
    --cc=nfs@lists.sourceforge.net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.