[Gluster-users] NFS crashes under load

[Shehjar Tikoo]

Thanks. I'll be looking into it. I've filed a bug at:

http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=2061

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It seems the crash is easily reproduced on your setup. Can you please 
post the log from Gluster NFS process in TRACE log level to the bug?

Dan Bretherton wrote:
> I upgraded to GlusterFS 3.1 a couple of weeks ago and overall I am very
> impressed; I think it is a big step forward.  Unfortunately there is one
> "feature" that is causing me a big problem - the NFS process crashes
> every few hours  when under load.  I have pasted the relevant error
> messages from nfs.log at the end of this message.  The rest of the log
> file is swamped with these messages incidentally.
> 
> [2010-11-06 23:07:04.977055] E [rpcsvc.c:1249:nfs_rpcsvc_program_actor]
> nfsrpc: RPC program not available
> 
> There are no apparent problems while these errors are being produced so
> this issue probably isn't relevant to the crashes.

Correct. That error is misleading and will be removed in 3.1.1

Thanks
-Shehjar
> 
> To give an indication of what I mean by "under load", we have a small
> HPC cluster that is used for running ocean models.  A typical model run
> involves 20 processors, all needing to read simultaneously from the same
> input data files at regular intervals during the run.  There are roughly
> 20 files, each ~1GB in size.  At the same time this is going on several
> people, typically, are processing output from previous runs from this
> and other (much bigger) clusters, chugging through hundreds of GB and
> tens of thousands of files every few hours.  I don't think the
> Gluster-NFS crashes are purely load dependant because they seem to occur
> at different load levels, which is what leads me to suspect something
> subtle related to the cluster's 20-processor model runs.  I would prefer
> to use the GlusterFS client on the cluster's compute nodes, but
> unfortunately the pre-FUSE Linux kernel has been customised in a way
> that has thwarted all my attempts to build a FUSE module that the kernel
> will accept (see
> http://gluster.org/pipermail/gluster-users/2010-April/004538.html)
> 
> The servers that are exporting NFS are all running CentOS 5.5 with
> GlusterFS installed from RPMs, and the GlusterFS volumes are distributed
> (not repicated).  Two of the servers with GlusterFS bricks are actually
> running SuSE Enterprise 10; I don't know if this is relevant.  I used
> previous GlusterFS versions with SLES10 without any problems, but as
> RPMs are not provided for SuSE I presume it is not an officially
> supported distro.  For that reason I am only using the CentOS machines
> as NFS servers for the GlusterFS volumes.
> 
> I would be very grateful for any suggested solutions or workarounds that
> might help to prevent these NFS crashes.
> 
> -Dan.
> nfs.log extract
> ------------------
> [2010-11-06 23:07:10.380744] E [fd.c:506:fd_unref_unbind]
> (-->/usr/lib64/glusterfs/3.1.0/xlator/debug/io-stats.so(io_stats_fstat_cbk+0x8e)
> [0x2aaaab30813e]
> (-->/usr/lib64/glusterfs/3.1.0/xlator/nfs/server.so(nfs_fop_fstat_cbk+0x41)
> [0x2aaaab9a6da1]
> (-->/usr/lib64/glusterfs/3.1.0/xlator/nfs/server.so(nfs3svc_readdir_fstat_cbk+0x22d)
> [0x2aaaab9b0bdd]))) : Assertion failed: fd->refcount
> pending frames:
> 
> patchset: v3.1.0
> signal received: 11
> time of crash: 2010-11-06 23:07:10
> configuration details:
> argp 1
> backtrace 1
> dlfcn 1
> fdatasync 1
> libpthread 1
> llistxattr 1
> setfsid 1
> spinlock 1
> epoll.h 1
> xattr.h 1
> st_atim.tv_nsec 1
> package-string: glusterfs 3.1.0
> /lib64/libc.so.6[0x35746302d0]
> /lib64/libpthread.so.0(pthread_spin_lock+0x2)[0x357520b722]
> /usr/lib64/libglusterfs.so.0(fd_unref_unbind+0x3d)[0x38f223511d]
> /usr/lib64/glusterfs/3.1.0/xlator/nfs/server.so(nfs3svc_readdir_fstat_cbk+0x22d)[0x2aaaab9b0bdd]
> /usr/lib64/glusterfs/3.1.0/xlator/nfs/server.so(nfs_fop_fstat_cbk+0x41)[0x2aaaab9a6da1]
> /usr/lib64/glusterfs/3.1.0/xlator/debug/io-stats.so(io_stats_fstat_cbk+0x8e)[0x2aaaab30813e]
> /usr/lib64/libglusterfs.so.0(default_fstat_cbk+0x79)[0x38f2222a69]
> /usr/lib64/glusterfs/3.1.0/xlator/performance/read-ahead.so(ra_attr_cbk+0x79)[0x2aaaaaeec459]
> /usr/lib64/glusterfs/3.1.0/xlator/performance/write-behind.so(wb_fstat_cbk+0x9f)[0x2aaaaace402f]
> /usr/lib64/glusterfs/3.1.0/xlator/cluster/distribute.so(dht_attr_cbk+0xf4)[0x2aaaab521d24]
> /usr/lib64/glusterfs/3.1.0/xlator/protocol/client.so(client3_1_fstat_cbk+0x287)[0x2aaaaaacd2b7]
> /usr/lib64/libgfrpc.so.0(rpc_clnt_handle_reply+0xa2)[0x38f1a0f2e2]
> /usr/lib64/libgfrpc.so.0(rpc_clnt_notify+0x8d)[0x38f1a0f4dd]
> /usr/lib64/libgfrpc.so.0(rpc_transport_notify+0x2c)[0x38f1a0a77c]
> /usr/lib64/glusterfs/3.1.0/rpc-transport/socket.so(socket_event_poll_in+0x3f)[0x2aaac3eb435f]
> /usr/lib64/glusterfs/3.1.0/rpc-transport/socket.so(socket_event_handler+0x168)[0x2aaac3eb44e8]
> /usr/lib64/libglusterfs.so.0[0x38f2236ee7]
> /usr/sbin/glusterfs(main+0x37d)[0x4046ad]
> /lib64/libc.so.6(__libc_start_main+0xf4)[0x357461d994]
> /usr/sbin/glusterfs[0x402dc9]
> ---------
>