As Conrad noted, there are too many factors, might not be Networker related at 
all. We had a similar issue with Brocade FC switch - had to configure 
connection as point-to-point. You might want to look at the Tape Library 
release notes (i3.1 and change request 32897 in our case).

Sami

-----Original Message-----
From: EMC NetWorker discussion [mailto:NETWORKER AT LISTSERV.TEMPLE DOT EDU] On 
Behalf Of =sasha=
Sent: 12 April 2012 13:01
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Subject: [Networker] Networker slow with Quantum Scalari40

Thanks for the tip. I just ran tests. i40 speed seems to be like in the specs 
for all block sizes, in example:

testing 128kB blocks: 
        *** test using random data: 
                write returns 107 sec --> 78398 kB/s
                read returns 109 sec --> 76959 kB/s
        *** test using bigasm-like data: 
                write returns 81 sec --> 103563 kB/s
                read returns 76 sec --> 110376 kB/s
        *** test using copies of /usr/sbin/tape_perf_test in buffer: 
                write returns 65 sec --> 129055 kB/s
                read returns 60 sec --> 139810 kB/s
        *** test using 2:1 compressible data: 
                write returns 62 sec --> 135300 kB/s
                read returns 57 sec --> 147168 kB/s
        *** test using 3:1 compressible data: 
                write returns 50 sec --> 167772 kB/s
                read returns 38 sec --> 220752 kB/s
        *** test using 4:1 compressible data: 
                write returns 50 sec --> 167772 kB/s
                read returns 37 sec --> 226719 kB/s
        *** test using buffer full of zeros: 
                write returns 47 sec --> 178481 kB/s
                read returns 32 sec --> 262144 kB/s


I check Networker Performance Tuning guide, all mentioned parameters are 
already tuned correctly.

I am still curious why speeds I see when staging to tape from windows storage 
node are mostly 25MB/s and when staging from Networker server mostly 45MB/s. 
Tests suggest i40 can perform much faster then that.

+----------------------------------------------------------------------
|This was sent by smirkovic AT lts DOT rs via Backup Central.
|Forward SPAM to abuse AT backupcentral DOT com.
+----------------------------------------------------------------------

To sign off this list, send email to listserv AT listserv.temple DOT edu and 
type "signoff networker" in the body of the email. Please write to 
networker-request AT listserv.temple DOT edu if you have any problems with this 
list. You can access the archives at 
http://listserv.temple.edu/archives/networker.html or via RSS at 
http://listserv.temple.edu/cgi-bin/wa?RSS&L=NETWORKER

To sign off this list, send email to listserv AT listserv.temple DOT edu and 
type "signoff networker" in the body of the email. Please write to 
networker-request AT listserv.temple DOT edu if you have any problems with this 
list. You can access the archives at 
http://listserv.temple.edu/archives/networker.html or
via RSS at http://listserv.temple.edu/cgi-bin/wa?RSS&L=NETWORKER