who makes Compression and deduplication?

[verre]

If I have a physical direct-san-access (fc) proxy, the deduplication and compression are performed by the proxy on the source datastore...is it true?
Therefore the data that pass between the VMFS and the proxy has already been deduplicated and compressed?
Thank you!

[dellock6]

correct, deduplication and compression are done by the source datamover, that is the proxy (at least for backups...).

[Shestakov]

Hello Valentino,

the deduplication and compression are performed by the proxy on the source datastore...is it true?

Correct. Proxy performs on-the-fly deduplication and compression of data received from the source component.

Therefore the data that pass between the VMFS and the proxy has already been deduplicated and compressed?

Dataflow for backup job is: Disk > Backup proxy > Network > Backup repository > Disk. So data is deduplicated and compressed after backup proxy.
Tahnks.

[alanbolte]

I saw this post in the Forum Digest and wanted to clarify - deduplication actually has to be done in two steps because you can have multiple source proxies. So Proxy A reads data blocks from VM1, compresses them, and deduplicates them against other data blocks from the same disk, and sends it to the target (repository) datamover. Proxy B does the same thing for VM2. The target datamover then deduplicates between the disks for both VM1 and VM2.

If your concern is the amount of data moving between the datastore and the source proxy, the main limitation is CBT. Its use with incremental backups is fairly obvious, but with active full backups on block storage it will read only the blocks containing data; it won't have to read any zero blocks. VMware has not implemented that feature of CBT for NFS storage.