Hi, I have a two server setup that acts as SMB as well as NFS servers in active/active configuration managed by CTDB(http://ctdb.samba.org/).
The write performance is around 100MB/s per client however the read performance is only 0.6MB/s (using Iozone benchmark). I use Windows 2003 Server as CIFS client. Sometimes the read performance is good only from one of the CTDB managed Samba servers but not consistent when you restart CTDB + Samba. Raw network bandwidth between CIFS client and Samba is greater than 200MB/s. I tried changing the SO_RCVBUF and SO_SNDBUF size and smb.conf locking options. Tracing smbd indicates sendfile being used for read and no errors (-EINVAL or -EIO). Any idea what is contributing the overhead during the read operation? smb.conf is as follows: [global] workgroup = TESTDOMAIN2 realm = TESTDOMAIN2.LOCAL netbios name = CTDB-HEAD server string = Clustered CIFS security = ADS auth methods = winbind, sam password server = 172.16.2.25 private dir = /mnt/gpfs/CTDB_AD passdb backend = tdbsam log level = 1 log file = /var/log/samba/log.%m max log size = 10000 deadtime = 15 socket options = IPTOS_LOWDELAY TCP_NODELAY SO_RCVBUF=262144 SO_SNDBUF=262144 SO_KEEPALIVE use mmap = No clustering = Yes disable spoolss = Yes machine password timeout = 999999999 local master = No dns proxy = No ldap admin dn = cn=ldap,cn=Users,dc=testdomain2,dc=local ldap idmap suffix = dc=testdomain2,dc=local ldap suffix = dc=testdomain2,dc=local idmap backend = ad idmap uid = 5000-100000000 idmap gid = 5000-100000000 template homedir = /home/%D+%U template shell = /bin/bash winbind separator = + winbind enum users = Yes winbind enum groups = Yes notify:inotify = no idmap:cache = no gpfs:leases = yes nfs4:acedup = merge nfs4:chown = yes nfs4:mode = special gpfs:sharemodes = yes fileid:mapping = fsname force unknown acl user = Yes use sendfile = Yes mangled names = No blocking locks = No strict locking = No wide links = No vfs objects = syncops, gpfs, fileid large readwrite = yes oplocks = yes getwd cache = yes blocking locks = no [global-share] comment = GPFS File Share path = /mnt/gpfs/nfsexport read only = No inherit permissions = Yes inherit acls = Yes oplocks = yes Thanks in Advance, -Tim -- To unsubscribe from this list go to the following URL and read the instructions: https://lists.samba.org/mailman/listinfo/samba