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prgrm runs slower on 2.66ghz as compared to 1.5ghz !!!???

4 posts · originally from https://geek.digit.in/community/threads/prgrm-runs-slower-on-2-66ghz-as-compared-to-1-5ghz.80743/

tweety_bird_bunny
tweety_bird_bunny Original post #1
Feb 21, 2008 at 4:10 PM
i made a prgrm in c to find prime no till given no...
i recorded the time taken to find pr no till 1crore, using a stop watch

now on my laptop wid 1.5ghz centrino processor (504mb ram) time taken is =9.5 sec

but on my pc wid 2.66ghz p4 processor(496mb ram) , it takes 13 sec to do the same...

y is dis hapening, shudnt it take less time on 2.66 ghz processorr...
help me
L
Mar 18, 2008 at 5:56 PM
hi..
even though u are using a faster processor does not necessarily mean that yr program might run faster. the reason for this can be attributed to the many other programs that were runnin on yr system at the time u tested it out.
The amount of multitasking, leads to time slots alloted to various programs according to a round robin multi level scheduling policy.
what that means is cpu time given to yr program becomes lesser.. leading to slower execution.
i hope i answered yr question.
nileshgr
Mar 18, 2008 at 6:17 PM
hi..
even though u are using a faster processor does not necessarily mean that yr program might run faster. the reason for this can be attributed to the many other programs that were runnin on yr system at the time u tested it out.
The amount of multitasking, leads to time slots alloted to various programs according to a round robin multi level scheduling policy.
what that means is cpu time given to yr program becomes lesser.. leading to slower execution.
i hope i answered yr question.
+1
infra_red_dude
Mar 18, 2008 at 9:39 PM
i made a prgrm in c to find prime no till given no...
i recorded the time taken to find pr no till 1crore, using a stop watch

now on my laptop wid 1.5ghz centrino processor (504mb ram) time taken is =9.5 sec

but on my pc wid 2.66ghz p4 processor(496mb ram) , it takes 13 sec to do the same...

y is dis hapening, shudnt it take less time on 2.66 ghz processorr...
help me

hi..
even though u are using a faster processor does not necessarily mean that yr program might run faster. the reason for this can be attributed to the many other programs that were runnin on yr system at the time u tested it out.
The amount of multitasking, leads to time slots alloted to various programs according to a round robin multi level scheduling policy.
what that means is cpu time given to yr program becomes lesser.. leading to slower execution.
i hope i answered yr question.
+1

The second thing is that the Centrino platform (with Pentium M/ CD/ C2D proc.) has a better IPC rate and shorter pipelines than the P4 and hence is a better proc. More speed doesn't necessarily translate into better performance.