Forum Discussion

smileagain's avatar
smileagain
Level 4
11 years ago

bulk transfer?? block size??

About bulk transfer with secondary logging

To effectively use network bandwidth for replication, data is replicated to a disaster recovery (DR) site in bulk at 256 KB. This bulk data transfer reduces VVR CPU overhead and increases the overall replication throughput. With compression enabled, bulk data transfer improves the compression ratio and reduces the primary side CPU usage.

 

 

question

1.Smaller than 256k did before?

2.Did you send compressed 256k?

  • Hello,

    I didn't find the relevant documentation to provde that smaller than 256k was done before but the way new feature of 6.1 is explained that now the writes are batched untill they reach 256k which I would assume that previously the writes were of any size & sent in some format like 4k or 8k.

    Yes, as per release notes for 6.1, now the data is compressed. From 6.1 release notes

    VVR replication performance improvements using bulk transfer

    To effectively use network bandwidth for replication, data is replicated to a disaster
    recovery (DR) site in bulk at 256 KB. This bulk data transfer reduces Volume
    Replicator (VVR) CPU overhead and increases the overall replication throughput.
    With compression enabled, bulk data transfer improves the compression ratio and
    reduces the primary side CPU usage. Bulk data transfer is not supported with bunker
    replication, and in cross-platform replication

     

    This was also suggested in your another post:

    https://www-secure.symantec.com/connect/forums/storage-foundation-61-new-feature

     

    G

  • Hello,

    I didn't find the relevant documentation to provde that smaller than 256k was done before but the way new feature of 6.1 is explained that now the writes are batched untill they reach 256k which I would assume that previously the writes were of any size & sent in some format like 4k or 8k.

    Yes, as per release notes for 6.1, now the data is compressed. From 6.1 release notes

    VVR replication performance improvements using bulk transfer

    To effectively use network bandwidth for replication, data is replicated to a disaster
    recovery (DR) site in bulk at 256 KB. This bulk data transfer reduces Volume
    Replicator (VVR) CPU overhead and increases the overall replication throughput.
    With compression enabled, bulk data transfer improves the compression ratio and
    reduces the primary side CPU usage. Bulk data transfer is not supported with bunker
    replication, and in cross-platform replication

     

    This was also suggested in your another post:

    https://www-secure.symantec.com/connect/forums/storage-foundation-61-new-feature

     

    G