Slow down in zfs filesystem creation

Question

Solaris 10 10/09 running as VM on Vmware ESX server with 7 GB RAM 1 CPU 64 bit
I wondered if anyone had seen the following issue, or indeed could see if they could replicate it -
Try creating a script that creates thousands of ZFS filesystems in one pool.
For example -
#!/usr/bin/bash
for i in {1..3000}
do
zfs create tank/users/test$i
echo "$i created"
done
I have found that after about 1000 filesystems the creation time slows down massively and it can take up to 4 seconds for,each new filesystem to create within the pool.
If I do the same for ordinary directories (mkdir) then I have no delays at all.
I was under the impression that ZFS filesystem were as easy to create as directories (folders), but this does not seem to be the case.
This sounds like it could be a bug. I have been able to replicate it several times on my system, but need others to verify this.

Answer 1

Might be worth raising on the open solaris forums where theres a least a chance it will be read by a ZFS developer.