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RE: reduce compilation times?


>If your hard drive throughput is faster than your CPU, then you are correct
and it does not make any >sense.

>For example, if you are using a 25 MHz 68030 and a 15,000 rpm 8 GB cache
Seagate drive connected >through SCSI-3, the drive is probably able to
completely feed the CPU.

>However, if your hard drive throughput is slower than your CPU, then -j
makes sense.>

>For example, if your CPU is a single core Pentium 4 at 3.6 GHz, and your
hard drive is any ATA connected >IDE drive, then -j would help, since the
CPU would have many spare cycles to burn while waiting for the >hard drive
to feed it, so it could be busy working on another compiler concurrently.

I test with a core 2 and -j2 worked fine.... But I still do not know why it
does not work on p4.
Any way.... thanks





John (Eljay) Love-Jensen wrote:
> 
> Hi mahmoodn,
> 
>> I have single core, P4. So I think -j does not make any sense. Is it
>> right?
> 
> If your hard drive throughput is faster than your CPU, then you are
> correct and it does not make any sense.
> 
> For example, if you are using a 25 MHz 68030 and a 15,000 rpm 8 GB cache
> Seagate drive connected through SCSI-3, the drive is probably able to
> completely feed the CPU.
> 
> However, if your hard drive throughput is slower than your CPU, then -j
> makes sense.
> 
> For example, if your CPU is a single core Pentium 4 at 3.6 GHz, and your
> hard drive is any ATA connected IDE drive, then -j would help, since the
> CPU would have many spare cycles to burn while waiting for the hard drive
> to feed it, so it could be busy working on another compiler concurrently.
> 
> HTH,
> --Eljay
> 
> 

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