I'm having a hard time sizing my source WAN-Accelerator. It eats up all RAM (32GB currently) and then starts paging like mad.
This is my setup:
8 vSphere VMs backed up in three jobs, 7.5TB in total.
virtual Veeam B&R 9.5 backup Server on Windows 2012R2 with Wan Accelerator Source (4 Cores, 32GB, 300GB Disk on a FC Array with 10k spinning disks and 4GB Write Back Cache)
Backup Proxy is on a virtual Windows 7 OS, 24GB and 4 Cores
Currently the backup server and proxy are connected with a 1GBit/s LAN, this will change later to a 50MBit/s WAN link.
My largest Job is a ~3TB Fileserver with ~300GB change rate per day. I have just upgraded the backup Server from 16GB to 32GB and watched the behaviour when the Backup Copy Job for this Fileserver kicked in:
1. all available RAM is being filled up to 100%
2. Disk usage on C: jumps to 100%, caused by pagefile.sys (starting with writing ~75MB/s, it has now settled down to read 8MB/s, write 2MB/s)
3. Backup Copy Job has startet transferring data. Processing rate is ~300KB/s, the disk is read at 15MB/s from Daily Backup source. This is an iSCSI array with 0% active time
I don't think the job will ever finish at this rate.
How much ram is needed for the source WAN Accelerator? Currently the System drive is constantly at 100% utilisation and no data is being passed to the Target. Ressource Monitor Shows ~100 page faults per second for VeeamWANSvc.exe.
I also already had to resize the WAN Cache disk twice to accomodate the Cache size on the source side, C:\VeeamWAN is now at 200GB in Digests. This seems lot to me.