On Wed, 2 Apr 1997, Fred Ab wrote:
I do agree on two points above: 'administration' and 'reliability'. Upgrading the OS takes only a few minutes and so far the F200 has had 100% uptime. However, on the third issue 'performance', I'm experiencing slower (almost 50%) read performance from my F220 than from a Sun Sparc20 NFS server. This issue has been looked at by NetApp's and so far no solution or reason to this anomaly.
I also got lesser than expected performance when doing reading tests of large files (streaming a few 200MB files from the NetApp to some Sun Ultra clients) and, as you, I've had great support from NetApp people with lots of suggestions etc on things to try but still we never figured out why the filer didn't do better on this type of transaction. The filer is an F540, by the way, and I got it to read about 8.7MB/second unless my memory fails me. It should have been able to do better really, with two 100Mbps fast ethernet interfaces, running full duplex to a fast ethernet switch to which four Sun Ultra 170 machines were connected, acting as clients.
Anyhow, I dropped that test and instead I did a more 'life-like' test for my application (which is to have the NetApp host newsspool on a large Usenet news system) by having lots of small programs running on the Ultras and let these programs do small, almost random reads from some 15GB of data consisting of small files (Usenet news articles) on the Netapp. The NetApp handled this great - it did lots of NFS ops/second and served the simulated 'news readers' with articles at great speed. It didn't have to pump out data very fast really, maybe 4-5MB/second at the most. The things is that it handled many small accesses very well. My conclusion (which isn't too hard to arrive at without testing probably, if you stop and think for a moment) is that the Netapp works in most real situations with real applications because this is the way data is most commonly accessed (of course there are exceptions). I'm not interested in the NetApp's ability to stream 200MB files really - that's for product brochures maybe - but in how fast it actually serves the average request and in this it seems to do very well.
So my suggestion is, if you have the time - make up some test requirements that you want the filer to live up to and then ask to borrow a demo filer from NetApp for testing. I'm sure they have such. That's the by far best way of knowing if you want the filer or not and unless you have special demands (like you're doing audio/video apps and need to stream few but large files extremely fast) I'm sure you'll like it.
Regards,
/Ragnar, Algonet