ZFS Bug?

[jfr2006]

I've been noticing that has my file system s getting more and more full (currently volume1 has around 200GB free), the read and write speeds have become more and more slow..Is this a bug, or is a behavior of the ZFS file system?

 

[Tekkie]

Could it be that you are now accessing the outer rim of the disk platter meaning slower rotation speed and thus transfer? Search the web you will see that transfer speeds decrease for all drives when you fill the up.

 

[matthewowen01]

Could it be that you are now accessing the outer rim of the disk platter meaning slower rotation speed and thus transfer? Search the web you will see that transfer speeds decrease for all drives when you fill the up.

not really how zfs operates. data does not get packed in tightly like NTFS, you want it spread out sparsely so as your heads move around reading, there is always a place nearby to write. but you are right that drive speed is dependent on location on the platter.

long story short zfs (as do most file systems) start to slow around 50% capacity, zfs gets bad much faster than most file systems.

 

[Tekkie]

Why is ZFS more affected than others?

 

[matthewowen01]

it's copy on write so it must find a new location to write data even if it's just making changes to existing data.

 

[Tekkie]

Thanks that's what I had thought of as well, I assume this problem is more apparent with large files than it is with small or?