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<DIV dir=ltr align=left><SPAN class=684263818-18102007><FONT face=Arial
color=#0000ff size=2>We've been pretty happy with the
T2000's.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=684263818-18102007><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=684263818-18102007><FONT face=Arial
color=#0000ff size=2>The tape library is an IBM 3584, the tape drives are IBM's
4Gb FC LTO-3 drives, there's a dedicated 4Gb HBA for each drive, and everything
is connected to 4Gb McData switches.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=684263818-18102007><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=684263818-18102007></SPAN><SPAN
class=684263818-18102007><FONT face=Arial color=#0000ff size=2>We used to have
IBM's 2Gb FC LTO-3 drives, and with those the peak performance was around
165MB/s per drive. These 4Gb drives peak at around 265MB/s per drive,
though with all 3 tape drives active, we see throughput closer to 220MB/s per
drive...I'm guessing we're bottlenecked by the ports on our disk subsystem
at the moment, but since performance is more than acceptable we're not looking
to tune this any further - at least not until our LTO-4 drives are installed
next month ;).</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=684263818-18102007><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=684263818-18102007><FONT face=Arial
color=#0000ff size=2>-devon</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=684263818-18102007><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
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</DIV>
<DIV dir=ltr align=left><FONT face=Tahoma size=2><B>From:</B>
Karl.Rossing@Federated.CA [mailto:Karl.Rossing@Federated.CA] <BR><B>Sent:</B>
Thursday, October 18, 2007 6:10 AM<BR><B>To:</B> Peters, Devon C;
VERITAS-BU@mailman.eng.auburn.edu<BR><B>Subject:</B> Re: [Veritas-bu] Some info
on my experiences with 10GbE<BR></FONT><BR></DIV>
<DIV></DIV><FONT face=Arial color=#0000ff size=2></FONT><BR><TT><FONT
size=2>Devon,</FONT></TT> <BR><BR><TT><FONT size=2>Good to hear that T2000's are
screamers.</FONT></TT> <BR><BR><TT><FONT size=2>What are the library/tape drive
specs. Are the drives FC attached? or are they attached via scsi to the media
server?</FONT></TT> <BR><BR><TT><FONT size=2>Thanks,</FONT></TT> <BR><TT><FONT
size=2>Karl</FONT></TT> <BR><BR><TT><FONT size=2>> From:
veritas-bu-bounces@mailman.eng.auburn.edu [mailto:veritas-bu-<BR>>
bounces@mailman.eng.auburn.edu] On Behalf Of Peters, Devon C<BR>> Sent:
Wednesday, October 17, 2007 12:12 PM<BR>> To:
VERITAS-BU@mailman.eng.auburn.edu<BR>> Subject: [Veritas-bu] Some info on my
experiences with 10GbE</FONT></TT> <BR><TT><FONT size=2>> </FONT></TT>
<BR><TT><FONT size=2>> Since I've seen a little bit of talk about 10GbE on
here in the past<BR>> I figured I'd share some of my experiences...
</FONT></TT><BR><TT><FONT size=2>> I've recently been testing some of Sun's
dual-port 10GbE NICs on <BR>> some small T2000's (1Ghz, 4-core). I'm
only using a single port on <BR>> each card, and the servers are currently
directly connected to each <BR>> other (waiting for my network team to get
switches and fibre in place).</FONT></TT> <BR><TT><FONT size=2>> So far, I've
been able to drive throughput between these two systems<BR>> to about
7500Mbit/sec using iperf. When the throughput gets this <BR>> high, all
the cores/threads on the receiving T2000 become saturated <BR>> and TCP
retransmits start climbing, but both systems remain quite <BR>> responsive.
Since these are only 4-core T2000's, I would guess that<BR>> the 6 or
8-core T2000's (especially with 1.2Ghz or 1.4Ghz <BR>> processors) should be
capable of more throughput, possibly near line speed.</FONT></TT> <BR><TT><FONT
size=2>> The down side achieving this high of throughput is that it requires
<BR>> lots of data streams. When transmitting with a single data
stream, <BR>> the most throughput I've gotten is about 1500Mbit/sec. I
only got <BR>> up to 7500Mbit/s when using 64 data streams… Also, the
biggest <BR>> gains seem to be in the jump from 1 to 8 data streams;
with 8 <BR>> streams I was able to get throughput up to
6500Mbit/sec.</FONT></TT> <BR><TT><FONT size=2>> Our goal for 10GbE, is to be
able to restore data from tape at a <BR>> speed of at least 2400Mbit/sec
(300MB/sec). We have large daily <BR>> backups (3-4TB) that we would
like to be able to restore (not <BR>> backup) in a reasonable amount of time.
These restores are used to <BR>> refresh our test and development
environments with current data. <BR>> The actual backups are done with
array based snapshots (HDS <BR>> ShadowCopy), which then get mounted and
backed up by a dedicated <BR>> media server (6-core T2000). We're
currently getting about <BR>> 650MB/sec of throughput with the backups (9
streams on 3 LTO3 tape <BR>> drives - MPX=3 and it's very compressible
data).</FONT></TT> <BR><TT><FONT size=2>> Going off my iperf results, the
restoring this data using 9 streams <BR>> should get us well over
2400Mbit/sec. But - we haven't installed <BR>> the cards on our media
servers yet, so I have yet to see what the <BR>> actual performanee of
netbackup and LTO3 over 10GbE is. I'm hopeful<BR>> it'll be close to
the iperf results, but if it doesn't meet the goal<BR>> then we'll be looking
at other options.</FONT></TT> <BR><TT><FONT size=2>> -- <BR>> Devon Peters
_______________________________________________<BR>> Veritas-bu maillist
- Veritas-bu@mailman.eng.auburn.edu<BR>>
http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu<BR></FONT></TT></BODY></HTML>