Gene,
I think tmpfs/ramfs method would increase the performance of PostgreSQL
when workload is write-intensive.
Does pgbench issue write intensive queries ? Since I do not know the
detailed queries issued in pgbench, I am happy if you teach me.
Regards,
-- Hideyuki
Gene wrote:
I was curious to see how postgres would perform with wal on a tmpfs vs
disk here are some numbers I got from pgbench. Let me know if I did
something stupid, this is the first time I've used pgbench. The wal on
tmpfs method is not significantly faster.
[[ WAL ON TMPFS ]]
pgbench -i -s 10 -U postgres -d benchmark
...
pgbench -Upostgres -s 10 -c 10 -t 10000 benchmark
starting vacuum...end.
transaction type: TPC-B (sort of)
scaling factor: 10
number of clients: 10
number of transactions per client: 10000
number of transactions actually processed: 100000/100000
tps = 5817.693724 (including connections establishing)
tps = 5825.646441 (excluding connections establishing)
[[ WAL ON EXT2 14 U320 DRIVE RAID10 WITH BBU (same as data) ]]
pgbench -Upostgres -s 10 -c 10 -t 10000 benchmark
starting vacuum...end.
transaction type: TPC-B (sort of)
scaling factor: 10
number of clients: 10
number of transactions per client: 10000
number of transactions actually processed: 100000/100000
tps = 5653.187997 (including connections establishing)
tps = 5660.554438 (excluding connections establishing)
pgbench -Upostgres -s 100 -c 10 -t 10000 benchmark
starting vacuum...end.
transaction type: TPC-B (sort of)
scaling factor: 100
number of clients: 10
number of transactions per client: 10000
number of transactions actually processed: 100000/100000
tps = 5536.019864 (including connections establishing)
tps = 5543.834350 (excluding connections establishing)
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