[pve-devel] Speed up PVE Backup

[Martin Waschbüsch]

> Am 16.02.2016 um 10:32 schrieb Stefan Priebe - Profihost AG <s.priebe at profihost.ag>:
> 
> Am 16.02.2016 um 09:57 schrieb Martin Waschbüsch:
>> Hi Stefan,
> 
>>> This is PVE 3.4 running Qemu 2.4
>> 
>> To me this looks like the compression is the limiting factor? What speed do you get for this NFS mount when just copying an existing file?
> 
> Which compression? There is only FS compression on the target side
> involed. I'm not using any compression on the source side.

Sorry, reading the 26MB/s I just assumed it sort of HAD to be compressed for it to be so slow...
What kind of storage backend do you use for the images on the source side?
Can you dd a disk image from that backend to the nfs mount with good speed?

> Writing to the NFS is very fast:
> # du -sh /root/testfile
> 640M    /root/testfile
> 
> # dd if=/root/testfile of=/mnt/pve/vmbackup/dump/testfile bs=4M oflag=direct
> 159+1 records in
> 159+1 records out
> 671088620 bytes (671 MB) copied, 0,855779 s, 784 MB/s

That looks like there should be ample bandwidth. ;-)


Martin