On 11 Jan 00, at 18:42, Michael S. Keller wrote:
- Performance I'm getting? For sequential writes, like when I
create an oracle tablespace, I get between 15-20 MB/s. Random writes
NFS v2 and v3 handle writes differently. Which version do you use, do you use UDP or TCP and with what packet sizes?
I don't remember the specifics of all the combinations I tried, but I played with v2, v3, udp and tcp. I'm currently running v3 over udp with (i think) 32k blocksize. Performance didn't vary much reguardless of the settings - this supprised me. This is running across giga-bit ethernet with it's 1500 byte packet size limit.
When My F740 is running at 15-20mb/s it's cpu is bouncing around between 80% to 100%, so I think this is the practical sequential i/o load it can handle.
How many mount points do you use?
I've got about 6 mount points, but I have all the db files under one mount point.
NFS will block if you run everything through one mount point.
I don't understand this, but then there's so much I don't understand about NFS. This is something else Netapp needs to consider when selling a Netapp as a db disk subsystem. Were fairly good at using disk subsystems, but we have little experience with NFS.
Anyway, are you saying that a NFS mount point can only have one outstanding i/o across it at any point? From what I read each biod could have one outstanding i/o although the manual didn't say anything about mount points.
Thanks
Rick
---------------------------------------------------------------------- Richard L. Rhodes e: rhodesr@firstenergycorp.com Ohio Edison Co. p: 330-384-4904 f: 330-384-2514