aixperformancetuning
FIELD NAME VALUE COMMENTS Command Minperm% 10 vmo -p -o minperm%=5 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/O s 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 rfc1323=1 no -p -o sb_max=1310720 no -p -o tcp_sendspace=262144 no -p -o tcp_recvspace=262144 no -p -o udp_sendspace=262144 no -p -o udp_recvspace=262144 nfso -p -o nfs_rfc1323=1 nfso -p -o nfs_socketsize=60000 nfso -p -o nfs_tcp_socketsize=600000 vmo -p -o minperm%=10 vmo -p -o maxperm%=90 vmo -p -o maxclient%=90 vmo -p -o minfree=960 vmo -p -o maxfree=1024 vmo -p -o strict_maxclient=1 vmo -p -o lru_file_repage=0 vmo -p -o lru_poll_interval=10 ioo -p -o j2_maxPageReadAhead=64 ioo -p -o maxpgahead=64 ioo -p -o minpgahead=2 ioo -p -o j2_minPageReadAhead=2 ioo -p -o j2_maxRandomWrite=32 ioo -p -o maxrandwrt=32 ioo -p -o j2_nBufferPerPagerDevice=2048 ioo -p -o pv_min_pbuf=