LTO-8 Tapes and streaming (Case 02772195)

[mkretzer]

Hello,

we have a new LTO-8 Tape device and still have major issues reaching the maximum reachable tape speed.

The speed goes to an average of 139 MB/s. The thing is the tape drive can stream much faster and sometimes really reaches 300 MB/s.

Problem is that Veeam is always transferring only one file with one stream to the drive. DataMoverLocalFastPath=1 does not help at all and the transfer gets even slower. The storage can do much more (reading a single file with ~300 MB/s, reading 4 files at once at 1 GB/s) but since Veeam is only doing one stream it is all very slow!

Why does Veeam not allow multiple backup files to be transferred at the same time (especially with per-VM and multiple SOBR) ?? Just the normal disk latency of 5-10 ms is enough to slow the one stream down... I do not want to buy 400 TB SSD storage just to get tape backup working at a good speed...

Markus

[veremin]

Can you tell me how your media pool is configured? Especially, its parallel processing settings. Thanks.

[Dima P.]

Markus,

Your case was reviewed by our experienced support engineers. Most likely the issue is related to SOBR performance, so kindly, keep working with our support team as additional troubleshooting information is required to identify the root cause.

[mkretzer]

We use a GFS media pool. Since when is there a parallel processing with one drive?

[mkretzer]

Markus,

Your case was reviewed by our experienced support engineers. Most likely the issue is related to SOBR performance, so kindly, keep working with our support team as additional troubleshooting information is required to identify the root cause.

We will but it would not happen with more than one steam....