I use my laptop to execute the following sql, it's: mydb=# update _mcir_2597431_clusterid2 set clusterid = 3; UPDATE 104770 Time: 8666.447 ms
and on my pc: mydb=# update _mcir_2597431_clusterid2 set clusterid = 3; UPDATE 104770 Time: 27171.203 ms First I wondered whether the write speed on pc is lower than laptop, so i use a cp command to test a write speed: on my laptop: postg...@postgres-laptop:~$ time cp backup/soft/data\ mining/SPSS\ Clementine\ v11.rar develop/ real 0m19.403s user 0m0.032s sys 0m3.472s on my pc: postg...@postgres-laptop:~$ time cp backup/soft/data\ mining/SPSS\ Clementine\ v11.rar develop/ real 0m9.192s user 0m0.008s sys 0m1.708s so the writing speed on disk of pc is much faster than laptop, why the update sql command is much slower than my laptop? what's the reason causing such decrease?
