Copying on SSD cache drive slow & CPU intensive (DelugeVPN)

[MediaMaan]

Evening everyone.

 

I created a cache only folder called /incomplete.  This is for files that are downloading.

Once they are completed, DelugeVPN (Binhex version) copies them to /Downloads/complete/.  The /Downloads share has cache enabled.

 

When Deluge initiates a move, the CPU jumps up to at least 45% usage, often spiking higher, and the move operation takes a long time.  I would have thought copying from one SSD share to another would have been virtually instantaneous and required little CPU usage.

 

When I had a /Downloads/incomplete folder (on the same share), I didn't have the issue.

 

I wanted to keep the incomplete files on a different share so they didn't get written to the array under any circumsance - no point in spinning up the array for files still being worked on, even if they are stalled for a while.

 

Anyone know why moving the files across shares on an SSD would take so long?  Is there anything I can do, other than going back to using 1 share for both the /incomplete and /complete folders?

[itimpi]

You are correct in that moving files between shares on the SSD drive should have been virtually instantaneous so the fact it is not suggests something else is going on.

 

have you checked:

• that both the source and target DO finish up on the same SSD drive
• that there is not some additional action being taken (e.g. extracting or decompressing the download) that is taking the time.

[MediaMaan]

11 hours ago, itimpi said:

You are correct in that moving files between shares on the SSD drive should have been virtually instantaneous so the fact it is not suggests something else is going on.

 

have you checked:

• that both the source and target DO finish up on the same SSD drive
• that there is not some additional action being taken (e.g. extracting or decompressing the download) that is taking the time.

There is only 1 SSD cache in the system, so definitely the same SSD.

The /incomplete share is cache only (the SSD drive is the cache drive of course).

The /download share is not cache only, but is set to use cache for new files.  Could this be the problem?  I guess I can try and verify by locating a file that gets moved and seeing exactly where it ends up.  I think I had seen a way to check if files were on cache or in the array...

[itimpi]

18 minutes ago, MediaMaan said:

think I had seen a way to check if files were on cache or in the array..

 

You can click on the folder icon at the right hand end of a drive entry on the Main tab to browse the contents of a particular drive.   You can also go via the Shares tab and browse via the folder icon for that share - it will show you for each entry exactly what drive(s) is involved for any folder/file.

[MediaMaan]

4 hours ago, itimpi said:

 

You can click on the folder icon at the right hand end of a drive entry on the Main tab to browse the contents of a particular drive.   You can also go via the Shares tab and browse via the folder icon for that share - it will show you for each entry exactly what drive(s) is involved for any folder/file.

Thanks for the reminder of where to find the folder icon!

I double-checked, and everything is still on the cache drive.

So the files are downloaded to one share on the cache, but when they are moved by Deluge to another share on the cache, it is taking time (multiple minutes for a 6Gb file).

Now that files being written to the array are ruled out (unless Deluge is moving cache -> array -> cache for some reason), what else could be causing the slowdown?