So I finally setup a user share and I am copying some data (using the share) to the machine.  I am watching the web interface and I see the space going down on one of the drives and the writes and reads going up on the parity and storage drive but I don't see anything happening with the cache drive?  I have the cache drive enabled in the share settings.  Any ideas?

 

Thanks,

 

Neil

 

So I finally setup a user share and I am copying some data (using the share) to the machine.  I am watching the web interface and I see the space going down on one of the drives and the writes and reads going up on the parity and storage drive but I don't see anything happening with the cache drive?  I have the cache drive enabled in the share settings.  Any ideas?

 

Thanks,

 

Neil

 

Did you enable it on each share?  Did you set a minimum free space?  What specifically are your settings?

 

Joe L.

I only have one share that I am currently using.  I didn't set a minimum space.  Min. free space: is blank.  I don't understand this and I am using high water allocation currently.

 

Neil

 

I only have one share that I am currently using.  I didn't set a minimum space.  Min. free space: is blank.  I don't understand this and I am using high water allocation currently.

 

Neil

 

If you do not set it, I really don't know what the cache drive will use.  It is in kilobytes.  It should be set to a value that is slightly larger than the largest file you will transfer using the cache drive.  If you expect to transfer 5GB files you'll need to set the field to something like

6000000000

 

You will also need to enable the use of the cache drive on the specific user-share.  (there is a setting per share).

Lastly, if you are copying directly to the "disk" shares, the cache drive is not used at all, ever.

Min space on the share I need to set?!

Like I said I am copying to the share and I do have the cache enabled.  I just setup the cache drive and pre-cleared it and formatted it...

After you enable the cache drive for the share(s) I think you need to stop and start the array at least one time in order for the cache drive to actually be in use. It has something to do with how the userfs/sharefs is started.

 

Ok so I did as suggested and restarted the array and the cache drive is working!  The problem now is that the cache drive isn't really doing what i expected it to!

 

I filled up the drive and I am copying massive amounts of data to my new array. I got an error from the windows server I am copying from saying the disk is full.  Well that is true the cache disk is full but the array has plenty of room.  When or why isn't the cache drive off loading the data as it fills up?

 

Thanks!

 

Neil

 

Typically the cache drive is scheduled to move files late at night (2am), however the Management Console interface should have a "Move Now" button. Or maybe that's an unMenu feature.

 

That is just poor.  It should reach a threshold and move data! Had no one realized this yet?

You set the schedule for the cache drive.  It is part of the settings you control.  By default it is in the middle of the night when it will affect the usage of the server the least for those watching movies or playing their media collection.

 

It WILL NOT help when transferring massive amounts of data, since the data still has to be copied to the protected array and as you said, it will fill quickly... more quickly than it can be moved.

 

The reason you are out of space is simple.. you did not set the "min free" setting on the cache drive.  That in combination with the fact that windows starts each file transfer with an initial tiny file and appends to it.  You probably have room for the tiny file, but not the complete file, so starts the copy, but when it runs out of space, it fails.

 

The min-free should be set to a value larger than the largest single file you will transfer.  It is in kilobytes, so put a number like

6000000

for 6GB (If I did my math right)

 

Once there is no more space available on th cache drive, the cache drive will be bypassed until there is, and the files directly copied to the protected array.

This is why the cache drive is useless for transferring massive amounts of data.  There is no way for it to keep up and, in fact, it will slow down the eventual process since data has to be moved twice.  It is only good for smaller amounts of bulk transfer that will all fit on the cache drive.

 

To get the cache mover running more frequently change the default "schedule" to one that runs it hourly.  If there is nothing to move it will do nothing.

An hourly schedule is:

0 * * * *

instead of the default

 

a quarter hourly schedule would be

0,15,30,45 * * * *