Is there a way to speed up backup process ? My servers have quite beefy processors but even when it’s running a backup it only uses few percent of processors that are basically still sleeping ! Isn’t it possible to tell him to use up to a certain level of power or use all avalaible power ?
I hit since quite a time the limit of the backup process in term of time it takes I have quite a lot of customers with account reaching 1/2To of files in it !
What OS and versions of software are you using ? Without basic system details everyone will be guessing. Is this a scheduled backup or are you running it in the foreground via the GUI ?
Yep you are right, Ubuntu 20 and Debian 12 but no difference, for software it’s virtualmin of course
whatever scheduled backup, or running through the GUI is not making any difference.
I tried also to do it in tar or zip or tar.gz but not really much difference
well the problem is that quantity of storage I need is not financially manageable with SSD for now
Side question: would it be a possible workaround to create a new volume with dedicated SSDs as target for backups ? or it would not change anything considering that data to backup are on mechanical RAID system ?
or perhaps a dedicated volume on SSD for the temp directory of Virtualmin ?
You don’t store backups on SSD. You use SSD as temporary storage and your RAID as permanent storage for your backups. For temporary storage, even a 1 TB SSD is plenty.
well backups are exported by ftp to an other server or it’s not a backup
for temp 1To is clearly not enough space as I have as indicated before quite few accounts that have more than 1To of files in it !
To make it clear, I have to install a 2 or 4To SSD in server, setup Virtualmin to use both for temp files and backup destination, and it should speed up a lot the process right ?
Please understand, I refer not to the storage that is used to hold the backup after it is FTPed.
To speed up your backup before it is FTPed, you need to use fast(er) media as temporary storage and SSD will be faster than HDD for this. Of that there is no doubt.
This really has little to do with Virtualmin per se. You could have a paid chat with either @tpnsolutions or myself and we could take you through a deep dive of the backup process so that there is clarity about how a small SSD drive could speed up the entire backup process for you.
Please allow me to say something, which of course will have nothing to do with your topic. I’m sorry about that…
I realize that perhaps there are some groups that profit from supporting users with the open source platform that Webmin/Virtualmin has worked hard to build and create forums to learn from each other.
Of course, these components, they all have their own knowledge and free time. But to be honest, profiting from an open source platform, especially for this large community just for the purpose of putting money in their pockets, I am completely against.
Perhaps, somewhere in the Virtualmin management team, they saw this inadequacy, but they were afraid to say it If I were you and there are many people out there with unresolved errors, I would choose the purchase option. paid version and wait for support from Virtualmin. Either I’ll figure it out and fix the problem myself, or I’ll donate to the Virtualmin staff with the problem completely resolved.
You could try this from the command line and see if it helps. Also, if you schedule different backups for different users maybe they will all grab their own core?
I worked at a place that did a full rsync of some 90 servers over the weekend. Sometimes we barely got it to tape by the time Stone Mountain showed up.
But, yeah, drive speed can be the issue. You can do a drive speed test and calculate if the raid is the bottleneck.
CPU isn’t the limiting factor. Seems likely disks are.
You may find that for your specific use case (slow disks, huge data), Virtualmin backups may be a suboptimal solution. You might find something like rsync or similar is a better choice, though that has some risks (you only get one copy, in the usual case, so if you ever need to revert to “two backup cycles ago”, it’s not possible). There are tools like rdiff-backup that take rsync to the next level for backup purposes. It allows recovery of past files, while also maintaining a mirror of the backed up files as of the last backup.
That would be faster than Virtualmin domain backups, even if you’re using Virtualmin’s incremental domain backups.
To expand on the CPU thing, lest you don’t believe me: Backups are run with a high niceness level, so it won’t consume CPU needed by other tasks, but if CPU usage is low, that means nobody is using CPU and thus the backup processes can use as much as they want…if they don’t want more, they aren’t getting data from the disk fast enough to keep the CPU busy. You can’t force a disk to be faster with more CPU.
I will also mention that if this is a virtual machine, disks may be much slower than you think, depending on which drivers and configuration is being used. Generally the right virtio drivers will be present in the Linux kernel and will Just Work, but it’s certainly possible to misconfigure things and maybe the defaults of whatever is creating your VMs is suboptimal. Disk performance tuning was a much more important thing in the days of spinning rust. Since you’re still living in those days, you’ll need to make sure you’re getting the most out of that iron.
I assumed OP had already looked at top to find out CPU usage, since they said, “when it’s running a backup it only uses few percent of processors that are basically still sleeping”.
If that’s true, then knowing that the backup will already use as much CPU as it needs as long as nothing else needs it more, I know it can’t be CPU-bound, and thus must be disk-bound.
install both pigz and pbzip2 and then change the backup format to either paralell pbzip or paralell gzip…the backups will go much faster as the compression will switch from single threaded compression to multi threaded compression. this is not done by default at installation unfortunately.
that’s part of the problem…however definitely instlal pbzip2 and pigz as i mentioned earlier. This will at least eliminate the cpu as the bottleneck…but those mechanical drives are a potential huge performance issue as well. as others have mentioned run top and see if your i/o wait…not cpu…is spiking during the backups…if it is then you need to upgrade to ssd’s for better performance.
I have quite a lot of customers with account reaching 1/2To of files in it !
If I were you and there are many people out there with unresolved errors, I would choose the purchase option. paid version and wait for support from Virtualmin. Either I’ll figure it out and fix the problem myself, or I’ll donate to the Virtualmin staff with the problem completely resolved.