Date: Thu, 24 Mar 2005 14:17:31 -0800 (PST) From: Eli dart <dart@nersc.gov> To: FreeBSD-gnats-submit@FreeBSD.org Subject: kern/79214: iozone hurts tcp-based NFS Message-ID: <20050324221731.1F7CF11469@omega.nersc.gov> Resent-Message-ID: <200503242230.j2OMU2ZM070436@freefall.freebsd.org>
next in thread | raw e-mail | index | archive | help
>Number: 79214
>Category: kern
>Synopsis: iozone hurts tcp-based NFS
>Confidential: no
>Severity: serious
>Priority: high
>Responsible: freebsd-bugs
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: sw-bug
>Submitter-Id: current-users
>Arrival-Date: Thu Mar 24 22:30:02 GMT 2005
>Closed-Date:
>Last-Modified:
>Originator: Eli dart
>Release: FreeBSD 5.4-PRERELEASE i386
>Organization:
NERSC
>Environment:
System: FreeBSD omega.nersc.gov 5.4-PRERELEASE FreeBSD 5.4-PRERELEASE #0: Mon Mar 21 10:48:01 PST 2005 nickb@omega.nersc.gov:/usr/obj/usr/src/sys/OMEGA-STABLE-SMP i386
>Description:
iozone causes NFS server problems when using TCP-based NFS:
Mar 23 17:10:49 epsilon-new nfs server omega-nfs1:/data/flow: not responding
Mar 23 17:10:49 epsilon-new nfs send error 35 for server omega-nfs1:/data/flow
Mar 23 17:10:49 epsilon-new nfs server omega-nfs1:/data/syslog: not responding
Mar 23 17:10:49 epsilon-new nfs send error 35 for server omega-nfs1:/data/flow
Mar 23 17:10:49 epsilon-new nfs send error 35 for server omega-nfs1:/data/flow
Mar 23 17:10:49 epsilon-new nfs send error 35 for server omega-nfs1:/data/flow
Mar 23 17:10:49 epsilon-new nfs server omega-nfs1:/data/syslog: is alive again
Mar 23 17:10:49 epsilon-new nfs server omega-nfs1:/data/flow: is alive again
Mar 23 17:10:49 epsilon-new nfs server omega-nfs1:/data/flow: is alive again
Mar 23 17:10:49 epsilon-new nfs server omega-nfs1:/data/flow: not responding
Mar 23 17:10:49 epsilon-new nfs server omega-nfs1:/data/flow: not responding
Mar 23 17:10:49 epsilon-new nfs server omega-nfs1:/data/flow: is alive again
>How-To-Repeat:
client and server are connected via back-to-back em interfaces
(crossover cable, no switch).
em driver modified to increase transmit and receive descriptor counts.
Chipset version supports this.
#define EM_MAX_TXD 4096
#define EM_MAX_RXD 4096
set up NFS as follows:
===== client /etc/fstab =====
omega-nfs1:/data/flow /data/flow nfs rw,nodev,noexec,nosuid,noinet6,nfsv3,intr,-
U,-b,-r=32768,-w=65535 0 0
===== Server config =====
# nfs
rpcbind_enable="YES"
rpcbind_flags="-h ${nfs_addr1} -h ${nfs_addr2}"
rpc_lockd_enable="YES"
rpc_statd_enable="YES"
nfs_server_enable="YES"
nfs_server_flags="-t -n 8 -h ${nfs_addr1} -h ${nfs_addr2}"
mountd_enable="YES"
===== /etc/exports =====
/data/flow -maproot=nfsnobody:nogroup client-host
Run iozone on client as follows:
iozone 2048 32768 /data/flow/iozone/crunch
iozone version is 2.01
>Fix:
Use UDP for NFS.
>Release-Note:
>Audit-Trail:
>Unformatted:
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20050324221731.1F7CF11469>