aixperformancetuning

FIELD NAME VALUE COMMENTS Command Minperm 10 vmo -p -o minperm5 Maxperm 90 vmo Maxclient 90 Should always equal maxperm vmo minfree 960 120 x of cpu’s / memory pools Use the amount of cpu’s that smt creates Mimimum amount of memory that can be free. This is always free on the box vmo maxfree 1024 minfree maxpgahead* cpu’s Use the amount of cpu’s that smt creates Page stealer will free up memory until the value of minfree is reached vmo strict_maxclient 1 vmo lru_file_repage 0 vmo lru_poll_interval 10 LRU poll interval vmo tcp_sendspace 262144 Network tcp_recvspace 262144 Network udp_sendspace 262144 DB_BLOCK_SIZE * DB_FILE_MULTIBLOCK_READ _COUNT, but greater than 65536 Network udp_recvspace 262144 4 * udp_sendpace, but less than sb_max parameter Network rfc1323 1 Network sb_max 1310720 Must be udp_recvspace Network maxpgahead 64 This is the number of pages to prefetch. Must match Oracle dbfilemultiblockreadcount 8 default with 8K blocks 16 default with 16K blocks Take dbfilemultiblockreadcount and multiply it by 4 4k pages Maxfree – minfree should be maxpgahead ioo maxpgahead / j2_maxPageReadAhead 64 DB_BLOCK_SIZE * DB_FILE_MULTIBLOCK_READ ioo_COUNT numfsbufs 2048 ioo hd_pbuf_cnt / pv_min_pbuf aix 5.3 1024 ioo minpgahead 2 Should equal j2_minpagereadahead ioo minpgahead / j2_minpagereadahead 2 Max 2, DB_BLOCK_SIZE/4096 ioo j2_nBufferPerPagerDevice 2048 Tune J2_dynamicBufferPreallocation instead of this parameter. ioo j2_dynamicBufferPrealloca tion Run the “vmstat -v“ command several times over a period of 10-30 minutes during peak processing. If the number of “I/Os blocked with no fsbuf“ increases with time, you need to increase JFS2 buffers. Ioo maxuproc 2048 for non-rac 20000 for RAC This requires a reboot smitty system - Change / Show Characteristics of Operating System maxrequests 16384 Smit aio minserv 100 Per server smit aio maxserv 200 This is per CPU. Set 10 * number of logical disks. Monitor the actual number of aioservers started during a typical workload using the pstat or ps commands. If the number of active aioservers is equal to maxservers, increase maxservers. NOTE If Oracle uses RAW or ASM files, calculate number of disks for non ASM/RAW disks only. smit aio AIX PERANCE TUNING no -p -o rfc13231 no -p -o sb_max1310720 no -p -o tcp_sendspace262144 no -p -o tcp_recvspace262144 no -p -o udp_sendspace262144 no -p -o udp_recvspace262144 nfso -p -o nfs_rfc13231 nfso -p -o nfs_socketsize60000 nfso -p -o nfs_tcp_socketsize600000 vmo -p -o minperm10 vmo -p -o maxperm90 vmo -p -o maxclient90 vmo -p -o minfree960 vmo -p -o maxfree1024 vmo -p -o strict_maxclient1 vmo -p -o lru_file_repage0 vmo -p -o lru_poll_interval10 ioo -p -o j2_maxPageReadAhead64 ioo -p -o maxpgahead64 ioo -p -o minpgahead2 ioo -p -o j2_minPageReadAhead2 ioo -p -o j2_maxRandomWrite32 ioo -p -o maxrandwrt32 ioo -p -o j2_nBufferPerPagerDevice2048 ioo -p -o pv_min_pbuf