Slow Restore on FT

[PatS729]

Hello, 

I am running a restore over FT for FS. The backup for this FS works way faster than the restore speed.

Media Server : 5240 Appliance running 773

SIZE_DATA_BUFFERS_FT : 262144

NUMBERS_DATA_BUFFERS_FT : 16 ( i have tried usinig different values but no luck in tuning restore speed.)

Client : Solaris 11 runing NBU 773

The backup selection on source client is a NFS mount. backup works @ 200 Mbps average but restore to same NFS mount starts with 16 Mbps but gradually lows down to 3-4 Mbps.

Any suggestions pointers please.

Thanks.

[quebek]

Hi

What are the write speeds on this system locally? Can you test this? I would have checked the raid card cache settings - write one.... or spoken with your storage team if the LUN where this FS do reside is from SAN...

[PatS729]

The NFS i am running restore to is from ZFS storage and mounted to NBU client over NFS. Do you still want me to check cache settings ?

[quebek]

hmm NFS mounts and FT... ok.

so checking cache is not really needed... What is the write speed on this NFS  - can you test it... except FT there is also some Network involved - I assume 10Gbps since you did have 200MB/s read speeds.... what about writes to this nfs from this client itsefl without involving NBU...??

[tunix2k]

Hi,

additional to Quebeks suggestions to test the nfs write speed without NBU you should perform a FT restore to al local filesystem (extra zfs possible?). Both test will give a hint where to search for the root cause Ft or nfs or both in combination.

ciao

tunix2k

[PatS729]

thanks @tunix2k thats the same thing was on my mind. I am trying to get a local lun and then perform the restore.

However, i happend to discuss this with our storage admin and understood that the NFS mount is coming from a RAID5 ZFS volume. As we all know... RAID5 does not gives a super performance 70:30 (read:write) ratio is what i know.

I was also checking statistics which showd a slow write performance on RAID5. I think NBU is out of question for now.

Thanks for the help :)

[Nicolai]

Try setting NUMBER_DATA_BUFFERS_RESTORE_FT to 64 or 128.

There was a limit on the number of FT buffers before, don't know if that limitation has been lifted.

[PatS729]

@Nicolai I have tried increasing NUMBER_DATA_BUFFERS_RESTORE_FT to 64 but then job has failed with Status 83. I guess thats a limitaion now.

[JoseGomez]

My two cents, althought the document relates to VMware restore there are instructions on it to use a HD performance tester that could be useful for this case

https://www.veritas.com/support/en_US/article.TECH169860

Thank you,