Hi,

Jim Yes, in step 5 commands were executed on both nodes.

We did some more tests with opensolaris 2008.11. (build 101b)

We managed to get AVS setup up and running, but we noticed that performance was 
really bad.

When we configured a zfs volume for replication, we noticed that write 
performance went down from 50 MB/s to 5 MB/sec.

A few notes about our test setup:

*  Since replication is configured in logging mode, there is zero network 
traffic
*  Since rdc_bitmap_mode has been configured for memory, and even more, since 
the bitmap device is a ramdisk. Any data IO on the replicated volume, results 
only in a single memory bit flip (per 32k disk space)
* This setup is the bare minimum in the sense that the kernel driver only hooks 
disk writes, and flips a bit in memory, it cannot go any faster!

The Test

* All tests were performed using the following command line
# dd if=/dev/zero of=/dev/zvol/rdsk/gold/xxVolNamexx oflag=dsync bs=256M 
count=10

* Option 'dsync' is chosen to try avoiding zfs's aggressive caching. Moreover 
however, usually a couple of runs were launched initially to fill the instant 
zfs cache and to force real writing to disk
* Option 'bs=256M' was used in order to avoid the overhead of copying multiple 
small blocks to kernel memory before disk writes. A larger bs size ensures max 
throughput. Smaller values were used without much difference though
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