Hello,
I've recently upgraded from an LTO2 to an LTO4 tape drive system. We currently backup approximately 2.3TB of data on our weekly full backups. Utilizing LTO2, this averaged around 65 hours for completion.. roughly 32.5 to write, and another 32.5 to verify.
Currently, with the LTO4, this has almost been cut in half at 36 hours to complete (including verify). However, the way the numbers split are that it still takes approximately 30+ hours to do the backup, but the verify has increased tremendously. Backups are currently running at approximately 1.2GB/min, while the verifies are up to 6.8GB/min.
I assume that one of our bottlnecks is utilizing an ultra160 scsi card (Adaptec 39160). I was under the impression that the card supported 160MB/sec transfer/throughput speeds. This seems adequate enough to get the type of writing gains I was anticipating (160MB/sec = 9.6GB/min [perfect world]).. I was hoping to at least pull off 3-4GB/min.
Since I'm not altogether current on scsi / tape throughputs, I'm looking for input which may contribute to getting faster writing speeds. I've made some changes to the configuration as far into buffers etc:
BLOCK SIZE: 64K
BUFFER SIZE: 1024K
BUFFER COUNT: 30
HIGH WATER COUNT: 15
I also tried it with the original (64K, 64K, 10, 0) and got the same exact throughput rate.
I've got 11d running on a 2003 server with the latest drivers installed. Any suggestions to increase the write speed? I'm open to getting a 360 card, but if anyone can let me know what kind of throughput they are seeing with that card it would be appreciated.
Thanks
Message Edited by jimsu on
06-24-2008 12:02 PM
