Hume size of zfs-fuse on N5200

[gduprey]

Howdy,

I've been running an N5200 with firmware 2.1.9 and 5 1.5TB disks (in a RAID-5 config -- 5.5TB useable) for about a month. I've also upgraded the system RAM to 1GB. The sysetm run SAMBA and NFS mounts and, using the installed RSYNC module, makes periodic backups of other machines (using the RSNAPSHOT scripts to keep multi-snapshots). The entire RAID array is formatted as a single file system.

I'm noticing awful delays with NFS mounts *sometimes*. Most of the time, accessing NFS mounts is instant, but a few times a day, there are delays of 10-30 seconds (after which it's fine). Watching memory use on the N5200, it seems most of the 1GB of RAM is in use (and not much is buffers -- I know that can skew your view if not paying attention to it) and when I look in detail, there is a process called "zfs-fuse" that is using up to and in excess of 400MB of RAM itself.

I suspect this is related to the ZFS file system, but any idea why the hell it has to use so much RAM? I suspect the size of this and the fact that it's likely connected to the ZFS filesystem and thise usually full resident is kicking other things out, like the NFS daemons. When I access them, the daemons have to swap back in and that takes a while. I'd figure a 1GB system wouldn't be doing much swapping, but I'm sure it does.

My question is -- is there any way to get the zfs-fuse process to release or not even consume so damn much RAM?

The problem is that as things are, it's really annoying the heck out of folks as their workstations freeze for 30 seconds at a time at random times (likely related to after a full rsync backup occurs, but not always).

Any pointers or thoughts would be appreciated!

Gerry