Technique - optimisation | Pb de performance ????

Par chris le 24/11/2006 - 12:49

Bonjour,

Ma configration Blade Center IBM lame Xeon 64bits 4G de mémoie
Suse Linux Enterprise Server 9
Postgresql 8.1.4 compilé sur la machine

Je viens de faire des benchs avec l'outils livré pgbench et les résultats que j'obtiens me semble bizarre ......

machine@lame:/usr/local/pgsql/bin> pgbench -c 100 -t 20 bench
starting vacuum...end.
transaction type: TPC-B (sort of)
scaling factor: 1
number of clients: 100
number of transactions per client: 20
number of transactions actually processed: 2000/2000
tps = 168.313219 (including connections establishing)
tps = 171.886088 (excluding connections establishing)
machine@lame:/usr/local/pgsql/bin> pgbench -c 100 -t 20 bench
starting vacuum...end.
transaction type: TPC-B (sort of)
scaling factor: 1
number of clients: 100
number of transactions per client: 20
number of transactions actually processed: 2000/2000
tps = 135.645557 (including connections establishing)
tps = 137.996578 (excluding connections establishing)
machine@lame:/usr/local/pgsql/bin> pgbench -c 100 -t 20 bench
starting vacuum...end.
transaction type: TPC-B (sort of)
scaling factor: 1
number of clients: 100
number of transactions per client: 20
number of transactions actually processed: 2000/2000
tps = 111.664327 (including connections establishing)
tps = 113.250559 (excluding connections establishing)
machine@lame:/usr/local/pgsql/bin> pgbench -c 100 -t 20 bench
starting vacuum...end.
transaction type: TPC-B (sort of)
scaling factor: 1
number of clients: 100
number of transactions per client: 20
number of transactions actually processed: 2000/2000
tps = 98.277693 (including connections establishing)
tps = 99.465938 (excluding connections establishing)
machine@lame:/usr/local/pgsql/bin> pgbench -c 100 -t 20 bench
starting vacuum...end.
transaction type: TPC-B (sort of)
scaling factor: 1
number of clients: 100
number of transactions per client: 20
number of transactions actually processed: 2000/2000
tps = 86.019308 (including connections establishing)
tps = 86.939523 (excluding connections establishing)
machine@lame:/usr/local/pgsql/bin> pgbench -c 100 -t 20 bench
starting vacuum...end.
transaction type: TPC-B (sort of)
scaling factor: 1
number of clients: 100
number of transactions per client: 20
number of transactions actually processed: 2000/2000
tps = 76.280502 (including connections establishing)
tps = 76.993547 (excluding connections establishing)
machine@lame:/usr/local/pgsql/bin>

A chaque fois que je relance (les uns derrière les autres) les résultats se détériorent ......

J'ai recommencé 2h après et au premier test les résultats sont revenus au meilleures valeurs......

je n'ai pas refait plusieurs essais, la machine étant en prod

Une idée ?????

Merci d'avance