Mike Ault wrote:
> "Ivan Vasquez" <ivan_at_looker.itos.uga.edu> wrote in message news:<c4f3eo$2je$1_at_cronkite.cc.uga.edu>...
>
>>Yes Mike, I have both, and for the interconnect I have entries on
>>/etc/hosts.
>>
>>Right now I'm considering tweaking the sysctl.conf as Daniel has suggested.
>>Any other suggestions are welcome. I would also like to hear if others have
>>had the same issues.
>>
>>Ivan.
>>
>>"Mike Ault" <mikerault_at_earthlink.net> wrote in message
>>news:37fab3ab.0403301206.470e1965_at_posting.google.com...
>>
>>>"Ivan Vasquez" <ivan_at_looker.itos.uga.edu> wrote in message
>>
>> news:<c4aafk$897$1_at_cronkite.cc.uga.edu>...
>>
>>>>I'm testing a 2-node Linux RAC installation that's performing poorly
>>
>> under
>>
>>>>certain circumstances. The cluster is using 1G NICs as interconnect. I
>>>>already know I'm not supposed to ask for great performance out of it,
>>>>however the interconnect's capacity is far from reached whenever I
>>
>> notice
>>
>>>>bad performance.
>>>>
>>>>Here is the behavior:
>>>>
>>>>With only one instance up, any query runs quickly, as expected.
>>>>
>>>>With both instances up, I connect to instance A, run a long query (say,
>>>>30-seconds) and it runs normally. At this point I assume instance A has
>>>>cached some or all the blocks used for the query.
>>>>
>>>>Then I connect to instance B and issue the same query as above. Rows are
>>>>returned intermittently, up to 4-second delays in between. I assume in
>>
>> this
>>
>>>>case RAC is trying to ship whichever buffers are found in instance A
>>
>> instead
>>
>>>>of reading from disk. No DML activity is going on, it's just me and the
>>>>database.
>>>>
>>>>What confuses me is that I don't see much traffic thru the interconnect,
>>
>> and
>>
>>>>CPU and disk utilization are far from high. Using vmstat I see increased
>>>>context switches, but they are just as high as those in the instance
>>
>> that
>>
>>>>runs fine! I have read note 181489.1 but haven't found much help from it
>>
>> and
>>
>>>>wonder if it's something else inherent to my architechture (i386).
>>>>
>>>>Thanks in advance for any clues.
>>>>Ivan.
>>>
>>>Of course I mean a private interconnect and public network...not to
>>>confuse the more literal of the group...
>>>
>>>Mike
>
>
> Ivan,
>
> I tried to send you some tuning ideas, but your email bounced back as not found.
>
> Mike
Ask him about his hardware and configuration ... before going too
far down that road. I've had feedback that his issues are not RAC
issues.
--
Daniel Morgan
http://www.outreach.washington.edu/ext/certificates/oad/oad_crs.asp
http://www.outreach.washington.edu/ext/certificates/aoa/aoa_crs.asp
damorgan_at_x.washington.edu
(replace 'x' with a 'u' to reply)
Received on Fri Apr 02 2004 - 20:56:53 CST
