Large files and SSD Cache - Question/feature request

[Spider99]

Problem

 

I have my nightly backups (Veeam) for each machine copied to my DP server each night but as these files created by Veeam just grow in size over time (no shrink option other than restart the backup history?) they become very large.

 

Recently a single file was getting into the 200GB range before i reset the history (i.e. start again)

 

When the files are updated they are stored on my NAS and then copied to my DP Server via SyncBackPro 

 

The copying is fine and not any issue.

 

Question

 

When the backups are copied to my DP server they tend to fill up the cache (4x 256GB drives with real time duplication) then a rebalance occurs sometime later and the data is moved to the archive drives - this works fine.

 

So is there anyway for large files to bypass the ssd cache and get written to the archive disks directly (accepting the copy might be slower) without disabling the ssd cache for "other" files

 

I guess i am asking for an exception list for the ssd cache by size/type of file?

 

I dont think this is possible but would like to be proved wrong

[Christopher (Drashna)]

Yes, absolutely. 
 
First, this happens "naturally" when the SSD drives are filled path the percentage specified (75% by default). 
 
Second, you can use the file placement rules to allow a specific folder (or extensions) to be placed only on the archive drives. This does require changing the balancer settings, though:

Uncheck the "File placement rules respect real time file placement limits set by the balancing plug-ins"

http://stablebit.com/Support/DrivePool/2.X/Manual?Section=Balancing%20Settings

 

This will allow the file placement rules to violate the real-time placement limits set by the SSD Optimizer balancer plugin.

[Spider99]

ok will give it a try

 

oh and the 75% fails every time if the next file to be copied is bigger than the remaining "space" rather than just going straight to the archive drives 

[Spider99]

This appears to be working

 

But have an associated issue

 

i applied a rule to one folder - and turned off the ssd drives - also un checked the "...repect real time..." option as suggested

 

this initiated a re-balance as expected but...

 

now the pool is moving over a TB of files from archive drive to archive drive for no reason - the ssd's were empty so had none of the files of the folder in question

 

Any idea whats going on?

 

Only have ssd opt and scanner plugins active

[Christopher (Drashna)]

Any disks showing up as "Damaged" in StableBit Scanner? 

 

Also, any rules targetting the specific drives?

[Spider99]

nope no errors (all drives just been through their monthly scan) and the only rule is for a directory

 

so it should not do this - correct?

 

It finished its balance and has not done it again but it move about 1.3TB which is less than the size of the directory ~ 900GB as i thought it might be moving the directory to another drive etc but not sure