Forum Discussion

NBU2010's avatar
NBU2010
Level 6
10 years ago

Performance issue on Disk Storage Unit

Dear Forum,

Backing up data on disk storage (SAN - VNX) space getting very less performance speed.

Speed is only 6-7 MB per stream and there is 18 streams in each backup job.

I am on Solaris 11 Master/Media and Client is W2K12 R2.

Whereas on the same setup when i backup some different data over tape the speed is around 40-50 Mbps per stream.

Following is set on Media  server

Number Data Buffers : 64

Size Data Buffers : 256

Is there any other paramater to be set for Disk Storage Unit for high performance.

7.6
Backing Up
Backup and Recovery
NetBackup
Solaris
  • Nicolai's avatar
    Nicolai
    10 years ago

    You can expect to get 75MB/sec per 4+1 stripe sustained (Write cache can cheat you).

    Doing more than 70MB/sec require striping across LUN volumes combining the write capability of multiple LUN's.

    Try reducing the number of concurrent write steam to disk to see if performance increases.

  • NBU2010's avatar
    NBU2010
    Level 6
    10 years ago

    Searching more on this, i came across NUMBER DATA BUFFERS DISK and Size, that i have set to 64 & 512.

  • RiaanBadenhorst's avatar
    RiaanBadenhorst
    Level 6
    10 years ago
    Whereas on the same setup when i backup some different data over tape the speed is around 40-50 Mbps per stream.<<< why not try backup the slow data to tape and compare? Stating that other data is quick is pointless. The data is not the same, so your logic proves nothing.
  • Marianne's avatar
    Marianne
    Level 6
    10 years ago

    I am battling to understand what exactly the data path is.

    If Master/Media and Client is W2K12 R2 where does Solaris 11 fit in the picture? 

    Are you backing up clients across the network? 
    Which type of NIC in the master/media server?

    If you have a 1 Gb NIC in the media server, then 6-7MB/sec * 18 streams give a  total throughput of over 100MB/sec - the max that a 1GB NIC can accommodate....

     

  • Nicolai's avatar
    Nicolai
    Moderator
    10 years ago

    How is the storage prsented from the VNX, as LUN in a raid pool or dedicated 4+1 stripes ?

  • NBU2010's avatar
    NBU2010
    Level 6
    10 years ago

    Yes, i am backing up Exchange data over network on this Solaris Media server havaing 10GB NIC.

    and yes the VNX is presented as LUN dedicated 4+1 stripes.

  • Nicolai's avatar
    Nicolai
    Moderator
    10 years ago

    You can expect to get 75MB/sec per 4+1 stripe sustained (Write cache can cheat you).

    Doing more than 70MB/sec require striping across LUN volumes combining the write capability of multiple LUN's.

    Try reducing the number of concurrent write steam to disk to see if performance increases.

  • Marianne's avatar
    Marianne
    Level 6
    10 years ago

    Log folders to troubleshoot NBU transfer rates:

    On media server: bptm

    On client: bpbkar

    Always best to use OS and network utilities to test all components in the backup path:
    1) Read speed from disk on the client 
    2) Write speed to backup storage on the media server
    3) Network transfer between client and media server

    See: 

    The NetBackup Backup Planning and Performance Tuning Guide, Release 7.5 and Release 7.6 
     http://www.symantec.com/docs/DOC7449

     

  • NBU2010's avatar
    NBU2010
    Level 6
    10 years ago

    Yes ...logged the folders...but no improvement seen for further analysis.

  • Marianne's avatar
    Marianne
    Level 6
    10 years ago
    The purpose of the logs is to determine where the bottleneck is. Check the initial buffer setup and the result at the end where 'waited for full/empty buffers ' is logged.