Speed up Azure files sync - pegged at 20 Mbps download

Viraj Talpade 1 Reputation point

We're doing a storage sync from Azure Files down to an on-prem server (Win Server 2019 VM on ESXi host). I notice that the download ranges between 17 - 25 Mbps but never over that range. NICs are gig-capable.

Also see that every 24-hours there's a spike in sync activity around 5:30 am PST where it processes about 20 GB of data. Then it dies down for the rest of the day.

We have a dedicated 1 Gbps pipe just for this sync. Any way I can improve network performance so it isn't pegged to the 20 Mbps network speed?

Azure Files
Azure Files
An Azure service that offers file shares in the cloud.
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  1. deherman-MSFT 33,141 Reputation points Microsoft Employee

    @Viraj Talpade
    For more information available on the performance expectations of Azure File Sync you should check this document. Likely the limitation is related to the need to sync smaller files. I expect if you tested with larger files you would see more throughput. You might find it helpful to look at the number files synced in Azure Monitor and compare with the documented expectations.

    The object throughput approximately scales in proportion to the number of sync groups on the server. Splitting data into multiple sync groups on a server yields better throughput, which is also limited by the server and network.

    The object throughput is inversely proportional to the MiB per second throughput. For smaller files, you will experience higher throughput in terms of the number of objects processed per second, but lower MiB per second throughput. Conversely, for larger files, you will get fewer objects processed per second, but higher MiB per second throughput. The MiB per second throughput is limited by the Azure Files scale targets.

    Hope this helps! Let us know if you have further questions or issues and we will be happy to assist.


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  2. Viraj Talpade 1 Reputation point

    @deherman-MSFT , thank you so much for the prompt response. I will definitely review the linked document. As a start, I've disabled the other sync group that uploaded to Azure Files. I'll see if that helps. Any thought on why we see a spike of 20 GB every morning about 5:30 am PST? Thank you again!

  3. Viraj Talpade 1 Reputation point

    That's probably it! Can I use this process to speed up the change detection?