Tape blocksize

[dweb]

Hi guys,

any chance to increase the tape blocksize?
We have a LTO4 and only about 50-70mb/s... which is way too low.

The local RAID which is storing the backup files (which are duplicated to tape) is running at about 600mb/s with 256kb blocks.. - so this is not the bottleneck.

Greets

[veremin]

We have a LTO4 and only about 50-70mb/s... which is way too low.

Hi, Daniel, is this a speed of tape job? What type of job it is file to tape or backup to tape one? Also, what component is indicated as bottleneck? Thanks.

[dweb]

Hi,

thanks for the answer.

The Tape-Job identifies the Target as bottleneck.
Also it is a backup to tape job.
Yes, this is the speed of the tape job.

Greets

[mazur1000]

I have the same problem. When backup to tape speed from 50 to 100 MB per second. When copying to another disk rack 200. bottleneck is Network. tape lto 6

[Dima P.]

Hello,
As far as I am concerned, data block size in tape functionality is set automatically according to output from tape library during session start.

In order to improve the tape library performance (in case the bottleneck is target), make sure the hardware compression on the tape job is disabled.

Also, I can say that we are awaiting for tape performance improvements in the upcoming major release, meanwhile if you are experiencing performance issue that heavily impact your infrastructure – please, open a support case. Thank you.

[dweb]

Any release date known? v8 then? or v7.1 or something like that?

And yes, hardware compression is and was disabled.

Very disappointing.

[Dima P.]

Daniel,

No release date yet, but improvements we are talking about will be included in next major version of the product. Thank you.

[siluro]

We are experiencing a similar scenario with our Dell TL4000 library connected via iSCSI. Veeam jobs run at about 45-50 MB/s. Dell support were able to get a much better transfer rate using their testing tools at a 256 KB blocksize. Their advice was to "increase tape drive block size in your backup software".

[ChrisPriest]

Hi All,

We are currently evaluating Veeam B&R 7, on the whole, I love the product, zero failures and very reliable.

My only concern is the tape backup speed, I am using a Backup to Tape job, backing up the Backup Job (Disk) to tape. I have around 4.2TB to transfer to tape and it's only backing up at 32 MB/s, the drive is a Powervault 124T SAS with a 6Gb/s controller.

I know that tape support is new and the focus was on functionality, but I would have expected to see better tape throughput.

The Bottleneck is being identified as the target.

I am using the standard Microsoft Drivers under Windows 2008 R2

Does anyone have any ideas what I might do to increase performance?

Best Regards
Chris

[veremin]

Hi, Chris,

Your post has been merged into existing discussion regarding similar matter. So, please, take a look at the suggestions (disable HW compression) and general explanation provided above.

Thanks.

[ChrisPriest]

Hi,

Yes I have checked all the above, but I still only get a constant 32 MB/s, so far the tape job has been running for 30+ hours

[veremin]

As stated above, some enhancements over tape job performance are scheduled for the next release. In the meantime, are you archiving only one huge backup job or "4.2TB" is combined size of all "source" backup jobs? In the latter case, you can, probably, split the source backup jobs among different backup to tape ones and run them on different basis.

Besides, you can always open a ticket with our support team and let them confirm your environment (may be, there are some factors affecting tape job performance seriously).

Thanks.