Performance difference between int4 and int8 in PostgreSQL on 64 bit server -



Performance difference between int4 and int8 in PostgreSQL on 64 bit server -

assuming postgresql running on 64 bit server, performance difference between int4 (32 bit) , int8 (64 bit) column? manual states int4 more efficient int8, if underlying server 64 bit, there practical performance difference (in terms of (1) cpu, (2) memory , (3) storage)?

in terms of (1) cpu, (2) memory , (3) storage

put bluntly:

64 bits twice big 32 bits.

64 bits twice big 32 bits.

64 bits twice big 32 bits.

i recall thread in wp-hackers did few benchmarks. create table, fill in 1000000 rows. find, add, group, join, etc. don't recall specifics, indeed slower using int8 int4.

test=# create table int4_test (id int primary key); create table test=# create table int8_test (id bigint primary key); create table test=# insert int4_test select generate_series(1,1000000) i; insert 0 1000000 test=# insert int8_test select generate_series(1,1000000) i; insert 0 1000000 test=# vacuum analyze; vacuum test=# \timing on timing on. test=# select sum(i.id) int4_test natural bring together int4_test j i.id % 19 = 0; sum ------------- 26315710524 (1 row) time: 1364.925 ms test=# select sum(i.id) int4_test natural bring together int4_test j i.id % 19 = 0; sum ------------- 26315710524 (1 row) time: 1286.810 ms test=# select sum(i.id) int8_test natural bring together int8_test j i.id % 19 = 0; sum ------------- 26315710524 (1 row) time: 1610.638 ms test=# select sum(i.id) int8_test natural bring together int8_test j i.id % 19 = 0; sum ------------- 26315710524 (1 row) time: 1554.066 ms test=# select count(*) int4_test natural bring together int4_test j i.id % 19 = 0; count ------- 52631 (1 row) time: 1244.654 ms test=# select count(*) int4_test natural bring together int4_test j i.id % 19 = 0; count ------- 52631 (1 row) time: 1247.114 ms test=# select count(*) int8_test natural bring together int8_test j i.id % 19 = 0; count ------- 52631 (1 row) time: 1541.751 ms test=# select count(*) int8_test natural bring together int8_test j i.id % 19 = 0; count ------- 52631 (1 row) time: 1519.986 ms

performance postgresql integer

Comments

Post a Comment

Popular posts from this blog

iphone - Dismissing a UIAlertView -

iphone - Dismissing a UIAlertView - i set in app purchase app, , when user taps button, purchase started. basically, tap button, , depending on speed on net connection, waiting 10 seconds until new alert view comes asking if purchase product. user tap button multiple times since nil came up, , multiple purchase alert views come up. additionally, maybe seen user app bug. in end, problem. i want alert view come spinning wheel says "loading..." when users taps purchase button. problem is, how dismiss when new alert view comes asking user if want purchase product? if ([uialertview alloc] says: @"whatever apple's alert view says") { //dismiss "loading..." alert view here } i uncertainty work, input appreciated. thanks! you need have access alertview. can this. create alertview instance var in app delegate , when want show loading initialize instance var assign property , when want dismiss phone call [alertviewinstance d...
Read more

intellij idea - Update external libraries with intelij and java -

intellij idea - Update external libraries with intelij and java - simple plenty really. i'm using apache jars, i'll create changes jar's every often. these jars listed external libs in intelij (i.e classpath looking install dir of jar's). when create changes intelij doesn't seem know new implementation. have remove jar external library , re-ad it. does know have intelij picks changes automatically ? i've done clean , rebuild project had little effect. you can go preferences -> build, execution, deployment -> build tools -> maven -> importing , check box says import maven projects automatically . in mac, can command + shift + a , come in action reimport , click on reimport maven projects . intellij-idea
Read more

javascript - send data from a new window to previous window in php -

javascript - send data from a new window to previous window in php - i have image in main.php file : <img src="..\images\image.gif" class="cur" onclick="imgwin();"> when click on image below function has called : function imgwin() { imagewin=window.open("../pages/img.php","imagewin","toolbar=no,width=500,height=200,directories=no,menubar=no,scrollbars=yes"); } this function opens img.php in new window img.php file : <html> <head> <title>upload image</title> </head> <body> <form name="imgform" method="get" action="#"> address : <input type="file" name="imgurl" size="50"> description : <input type="text" name="description" size="50"> <input type="submit" value="sumbit...
Read more