My application runs 40% slower on a V880 than on a 6800. In comparing the kernel parameters between the two machines, I found SHMMAX set to 13.7G on the V880 and 3.5G on the 6800. Also the V880 has 32G memory and the 6800 has 10G. The SHMSEG parameter is set to 124 on both machines. Could this high value for SHMMAX on the V880 be causing the problem (maybe using more kernel memory than necessary)?
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Performance Tuning - SHMMAX
- Thread starter marcoben
- Start date
could be, but depends on the application:
how much IO it uses, how the 6800 was set up
(24 CPU vs 8 CPU?) or any other parameter
you did not mention.
Otherwise, I would play with the SHMMAX and
maybe a few other parameters; there is a
guide on kernel-tuning on sun; maybe helpfull.
matt
how much IO it uses, how the 6800 was set up
(24 CPU vs 8 CPU?) or any other parameter
you did not mention.
Otherwise, I would play with the SHMMAX and
maybe a few other parameters; there is a
guide on kernel-tuning on sun; maybe helpfull.
matt
The 6800 and 880 do not have the same architecture. Do you have the same amount of cache, same CPU speed, same amount of RAM, same hard drive RPM, etc ...
In any case a 6800 will always be somewaht faster than a 880 depending on the application. Too bad I.T. is not cash business
Luc Foata
Unix sysadmin, Oracle DBA
In any case a 6800 will always be somewaht faster than a 880 depending on the application. Too bad I.T. is not cash business
Luc Foata
Unix sysadmin, Oracle DBA
- Status
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