Re: forcing an nfs sync

Hi Neall,
On Tue, 11 Oct 2005 09:15:24 -0600 (MDT), Linux Doctor <NOSPAMusenet@xxxxxxxxxxxxxx> wrote:

Search lkml.org for "Cache invalidation bug in NFS v3 - trivially reproducible"
came up yesterday, might be something? (linux kernel mailing list)

>Follow-up from original poster (me):
>
>I used the sync option in the /etc/exports file of the server, along with
>no_wdelay, and clients still didn't see immediate changes in the file on
>the server. There was a definite lag (several seconds typically, if not
>more).
>
>Apparently, the server was syncing immediately as a result, but not the
>clients. What I ended up having to do was to add a actimeo option to the
>mount command (/etc/fstab) on the CLIENT side. This resolved the issue.

Okay, I have simple setup:

server:
/ 192.168.1.0/24(sync,rw,no_root_squash)
/home/share 192.168.1.0/24(sync,rw,no_root_squash)
/home/mirror 192.168.1.0/24(sync,ro)

client:
deltree:/ /home/deltree nfs noauto,user,hard,intr
deltree:/home/mirror /home/mirror nfs hard,intr
deltree:/home/share /home/share nfs hard,intr

I do linux-kernel testing, each target machine mounts /home/share,
from where they pickup latest kernel source and patches. I've never
noticed a lag from getting a new patch and being able to pick it
up from clients. Likewise, on each client reboot I write dmesg and
config to the server's /home/share, on server I move those files to
appropriate machine web page <http://bugsplatter.mine.nu/test/>.

>
>In my application, I don't have a lot of NFS traffic, but need to know
>quickly about changes in the files on the server. My tests showed that
>"sync" did not affect the overall throughput (as opposed to async), at
>least in my application. The massive amount of literature online seems to
>indicate that there is a cost with using "sync," but it's obviously
>application dependent and I didn't see any pentalty at all. Neall

Okay, I think that's the point I was trying to make, reliability before
speed? I have NFS 3 over TCP enabled, no ACLs, no selinux, as there's no
hostile user-base here (unless I'm in a bad mood :o) Reiserfs, if that
makes a difference. Server runs 2.4.31-hf6, clients run 2.4 or 2.6 latest
or development. All are Slackware 10.1 or later.

Cheers,
Grant.

.

Relevant Pages

  • Problem with popen
    ... Under linux x86 I'm running a stress test which opens some tcp server ... applications and then about 70 clients in each their thread. ... The server however is started as an async process using fork and then ... sync and async processes. ...
    (comp.unix.programmer)
  • Re: Domain Time Syncing
    ... may want to start with the event logs on the clients that don't work. ... problem of why the server wasn't sync'ing with an outside source. ... see if their time will sync to the PDC. ... "The time service detected a time difference of greater than 128 ...
    (microsoft.public.windows.server.active_directory)
  • Remote Connection Issue/Question
    ... I have and SBS 2003 R2 Std server with several XP Pro clients. ... off-line/sync folder with a folder on the server. ... network then just sync the folder (either manually or by scheduling at the ...
    (microsoft.public.windows.server.sbs)
  • Re: Problem
    ... branch office VPN that will tunnel the traffic or the clients in location B ... need to connect individually via VPN to the SBS server at location A. ... When I log in it says it can't sync the files to the domain so it will ... was in the old router which I had to reset. ...
    (microsoft.public.windows.server.sbs)
  • RE: Users Cant Access Documents on Server
    ... Thanks for using the SBS newsgroup. ... As well as we know, if a workstation would not access network shares, then ... Leave the Default Gateway of the internal NIC blank of the server box. ... Clients That Require SMB Signing ...
    (microsoft.public.windows.server.sbs)