# [SOLVED] Intel core 2 quad = makeopts="-j5"

## Joseph_sys

I can not find conclusive answer on Intel Core 2 Duo; should it be:

makeopts="-j5"

or 

makeopts="-j3"Last edited by Joseph_sys on Sat Sep 20, 2008 4:49 am; edited 3 times in total

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## overkll

IMO, -j3.  It's a 2 core chip.  Gentoo recommends number of procs +1 for MAKEOPTS.  Currently, Core 2 Duo's and Core 2's have no Hyperthreading, so I'd stick with -j3.

If they had Hyperthreading enabled, or if you had a Core 2 Quad, then -j5 would be the recommended setting.

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## Joseph_sys

 *overkll wrote:*   

> IMO, -j3.  It's a 2 core chip.  Gentoo recommends number of procs +1 for MAKEOPTS.  Currently, Core 2 Duo's and Core 2's have no Hyperthreading, so I'd stick with -j3.
> 
> If they had Hyperthreading enabled, or if you had a Core 2 Quad, then -j5 would be the recommended setting.

 

My mistake :-/ I have Intel core 2 quad

so, it will be "-j5" for me.

Now, I want to install 64-bit architecture do I download "amd64" or "ia64" ?

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## pappy_mcfae

If you have that much machine, you can crank j up to any ridiculous number you can imagine, and it will work. I use -j64 on my Core2 Duo, and -j32 on this machine. I use -j8 for my older laptop, as it only has 256 Megs of RAM, so it can't quite be overloaded like the newer stuff.

You know you've cranked it too hard when you use 95% of your memory, and 95 percent of swap, and the machine responds like a cadaver.

Blessed be!

Pappy

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## devsk

 *Joseph_sys wrote:*   

>  *overkll wrote:*   IMO, -j3.  It's a 2 core chip.  Gentoo recommends number of procs +1 for MAKEOPTS.  Currently, Core 2 Duo's and Core 2's have no Hyperthreading, so I'd stick with -j3.
> 
> If they had Hyperthreading enabled, or if you had a Core 2 Quad, then -j5 would be the recommended setting. 
> 
> My mistake :-/ I have Intel core 2 quad
> ...

 -j5 is ideal but you can go to -j6 as well and control the load on the system with -l8. So, if I were you I would use MAKEOPTS="-j6 -l8". I would say try different combos and see which works best for your hardware.

And you will download amd64.

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## Joseph_sys

 *devsk wrote:*   

>  *Joseph_sys wrote:*    *overkll wrote:*   IMO, -j3.  It's a 2 core chip.  Gentoo recommends number of procs +1 for MAKEOPTS.  Currently, Core 2 Duo's and Core 2's have no Hyperthreading, so I'd stick with -j3.
> 
> If they had Hyperthreading enabled, or if you had a Core 2 Quad, then -j5 would be the recommended setting. 
> 
> My mistake :-/ I have Intel core 2 quad
> ...

 

Thanks for input and suggestion, I'll try it.

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## Joseph_sys

 *devsk wrote:*   

> -j5 is ideal but you can go to -j6 as well and control the load on the system with -l8. So, if I were you I would use MAKEOPTS="-j6 -l8". I would say try different combos and see which works best for your hardware.

 

Where will I find more information on the second parameter "l8" ?

I'm just curious, what other settings are there.

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## overkll

 *Joseph_sys wrote:*   

> Where will I find more information on the second parameter "l8" ?
> 
> I'm just curious, what other settings are there.

 

```
$ man make
```

Interesting...  I may have to try with a AMD Turion RM-70 dual core.  "-j4 -l6" ?

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## username234

I have a core2 quad too.

Currently my make.conf settings are:

```
MAKEOPTS="-j9" 

DEFAULT_EMERGE_OPTS="--load-average=20 --jobs=16"
```

(The DEFAULT_EMERGE_OPTS only works for portage 2.2 and later I think... earlier versions I think will ignore this)

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## devsk

@username234: you better put -l8 in your MAKEOPTS, otherwise you will have *slower* builds, not faster. Remember context switches have a cost. And with 9 processes on 4 cpus, the context switch is a big chunk. Its like throwing your cpu cycles in the trash can. Moreover, -j9 is across all the emerge jobs. So, you are probably running 9*16=144 processes at a time in best parallelism scenario, taking your context switch cost way higher. You are stopping emerge from going beyond load 20 (which is way too high for quad core, 6 or 8 is probably sane), but you are not stopping make from going insane.

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