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We have this current settings.

myibm:root:/:>ioo -Fa |grep aio  
                    aio_active = 1  
                   aio_maxreqs = 65536  
                aio_maxservers = 30  
                aio_minservers = 3  
         aio_server_inactivity = 300  
              posix_aio_active = 0  
             posix_aio_maxreqs = 65536  
          posix_aio_maxservers = 30  
          posix_aio_minservers = 3  
   posix_aio_server_inactivity = 300  
                  aio_fastpath = 1 
                aio_fsfastpath = 1  
                 aio_kprocprio = 39  
              aio_multitidsusp = 1  
               aio_sample_rate = 5  
         aio_samples_per_cycle = 6  
            posix_aio_fastpath = 1  
          posix_aio_fsfastpath = 1  
           posix_aio_kprocprio = 39  
         posix_aio_sample_rate = 5  
   posix_aio_samples_per_cycle = 6   

We are just wondering about the setting on aio_active. Most of the documents show it as aio_active=0 .

The application and db running on this system is Oracle 10G.

Any ideas on this setting if it will help improve performance if it is change to 0.

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migrated from Apr 18 '11 at 18:48

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up vote 0 down vote accepted

aio_active is not really a tunable. It indicates whether or not the aio extension has been "loaded and pinned". If you see it as "1", then something loaded the AIO extension and is using it. See the ioo documentation.

This is what is generally recommended for Oracle. See Optimizing AIX 6.1 performance tuning for some discussion of the tunables related to asynchronous I/O.

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@Mat, thanks for your input. We are reviewing the ioo documentation and kindly help us understand this better. so it is safe to assume that by default it is set to 0 and the current value that we are seeing right now (1) was set by AIX itself? Can you give us advise if this necessary to change right now to 0 as we see high IO ops? – AlBouazizi Apr 18 '11 at 8:46

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