Del has given you the same analysis that I would have. I would arrive at the same numbers. Remember though that Del is talking about actual data backed up at 50MB/sec. So if your actual data in the database is 60% then the total time would be adjusted accordingly down from 16+ hours.
-----Original Message----- From: Del Hoobler [mailto:[EMAIL PROTECTED]] Sent: Friday, March 15, 2002 12:37 PM To: [EMAIL PROTECTED] Subject: Re: 2.8TB SQL Server Database Backup > I have a potential customer running a 2.8 TB SQL Server database on an > 8-way NT server. What can I realistically expect to achieve in > maximum backup throughput using TDP for SQL Server? > > Assume the 4-way Solaris TSM server has 8 AIT-2 tape drives dedicated > to getting this backup performed without any competing resource > constraints. FYI AIT-2 run at 6 MBps native and the cartridges are 50 > GB each. Joshua, Some of my thoughts on the subject... In some performance tests that were run, TDP for SQL achieved over 50MB/sec with 4 stripes...with plenty of CPU capacity still left on the SQL server. We believe we were being limited by the I/O subsystem on Windows. In any case, if the tape drives in this case have a throughput rate of only 6MB/sec, I think it possible that we can drive all 8 at that rate for an aggregate throughput of 48MB/sec (using 8 stripes). This would translate to approx 172 GB/hr which would require 16.3 hrs to complete a full backup of a 2.8TB database. If these drives have good hardware compression, then perhaps the overall throughput can be improved...but it seems that in our scenario, the I/O subsystem on Windows was the limiting factor. *** Disclaimer: I am not guaranteeing anything with these numbers... They are simply a statement of what we saw during performance testing. I hope they help. Thanks, Del ---------------------------------------------------- Del Hoobler IBM Corporation [EMAIL PROTECTED] - Leave everything a little better than you found it. - Smile a lot: it costs nothing and is beyond price.
