Futures - HAMMER comparison testing?

[Bill Hacker]

I'm guessing it will be a while yet before HAMMER is ready for this, but 
it seems to be moving fast - and cleanly - so...

. .. to the extent networked clustering AND inherent recoverablility are 
intended to be major strengths - to what comparable fs should we expect 
to look if we were to compare performance & features?

My own first impression includes:

- IBM's 'GPFS'  (hard for mere mortals to get access to a realistic test 
environment, but perhaps performance is well documented somewhere in a 
Redpaper?)

- Just-acquired-by-Sun 'Lustre' (an unknown to me)

- CMU's AFS (in ports. Has never seemed particularly magical to me..)

- Plan 9's Fossil/Venti (likewise, even when run 'native' - IMNSHO, 
actually no longer viable).

- Is NFS a realistic candidate in some incarnation?

Others? [1]

 and - eventual performance quite aside, should we be looking at stress 
test design [2], or are there benchmarks already appropriate?

Bill Hacker

[1] I don't know that ZFS *inherently* plays in the cluster yet - but 
Lustre was allegedly purchased in order to be worked in with ZFS so... 
'maybe soon'.

[2] Tracking ZFS from mailing lists gives me the impression that is has 
been relatively solid for PJD on small HDD and RAM. Likewise for Sun on 
massively greater RAM and HDD arrays.

BUT - that many of the reported problems are from folks in the 'tween 
decks' - i.e. larger arrays amd RAM than PJD reports as solid, but less 
available RAM-to-disk than Sun generally uses for real-world use.

So the question arises if HAMMER will

a) be overly sensitive to / hungry for - memory as a resource

b) if so, at least just slow-down when short-changed rather than crashing.

c) IF crashed, (or otherwise treated rudely) be more certain of 
trouble-free recovery than product 'x'.