[gentoo-user] Better CPU for compiling with gcc

[gentoo-user] Better CPU for compiling with gcc

[Stanislav Nikolov]

Dear Gentoo users,
I'm building a new PC. I have a budget of ~$550-$650. No GPU, no special case (I may use a card box), not even a hdd or ssd.
So, as you can see, it's pretty much "get the best CPU and mobo/ram that are compatible with it". The problem is, which is the best one. By "best" I mean to compile shit fast. My laptop with 3rd gen i5 compiles firefox for 40 minutes on average.

The most expensive Intel CPU is the skylake i7-6700k. But is it the best? Is there something from AMD that will perform even better? I can't find any benchmarks with AMD/Intel CPUs.
And how much does the mobo matter? Will a cheap $30 400W PSU power that thing?

Thanks

Re: [gentoo-user] Better CPU for compiling with gcc

[Mick]

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On Tuesday 10 Nov 2015 17:47:08 Stanislav Nikolov wrote:
> Dear Gentoo users,
> I'm building a new PC. I have a budget of ~$550-$650. No GPU, no special
> case (I may use a card box), not even a hdd or ssd. So, as you can see,
> it's pretty much "get the best CPU and mobo/ram that are compatible with
> it". The problem is, which is the best one. By "best" I mean to compile
> shit fast. My laptop with 3rd gen i5 compiles firefox for 40 minutes on
> average.
> 
> The most expensive Intel CPU is the skylake i7-6700k. But is it the best?
> Is there something from AMD that will perform even better? I can't find
> any benchmarks with AMD/Intel CPUs. And how much does the mobo matter?
> Will a cheap $30 400W PSU power that thing?
> 
> Thanks

I don't (yet) own a i7-6700k, but my 6 year old laptop with (1st generation) 
i7 Q720  @1.60GHz takes slightly less than yours:

     Sat Oct  3 14:35:40 2015 >>> www-client/firefox-38.3.0
       merge time: 36 minutes and 53 seconds.

     Fri Nov  6 09:10:06 2015 >>> www-client/firefox-38.4.0
       merge time: 38 minutes and 8 seconds.


In contrast a year old AMD A10-7850K APU is significantly faster:

     Sat Oct  3 19:40:48 2015 >>> www-client/firefox-38.3.0
       merge time: 17 minutes and 42 seconds.

     Fri Nov  6 08:41:02 2015 >>> www-client/firefox-38.4.0
       merge time: 18 minutes and 18 seconds.


I would also be interested to see compile times of more modern i7s and FXs, 
but bear in mind that in single core operations Intel is these days 
significantly better than AMD.

-- 
Regards,
Mick

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Re: [gentoo-user] Better CPU for compiling with gcc

[Stanislav Nikolov]

On 11/10/2015 08:17 PM, Mick wrote:
> On Tuesday 10 Nov 2015 17:47:08 Stanislav Nikolov wrote:
>> Dear Gentoo users,
>> I'm building a new PC. I have a budget of ~$550-$650. No GPU, no special
>> case (I may use a card box), not even a hdd or ssd. So, as you can see,
>> it's pretty much "get the best CPU and mobo/ram that are compatible with
>> it". The problem is, which is the best one. By "best" I mean to compile
>> shit fast. My laptop with 3rd gen i5 compiles firefox for 40 minutes on
>> average.
>>
>> The most expensive Intel CPU is the skylake i7-6700k. But is it the best?
>> Is there something from AMD that will perform even better? I can't find
>> any benchmarks with AMD/Intel CPUs. And how much does the mobo matter?
>> Will a cheap $30 400W PSU power that thing?
>>
>> Thanks
> I don't (yet) own a i7-6700k, but my 6 year old laptop with (1st generation) 
> i7 Q720  @1.60GHz takes slightly less than yours:
>
>      Sat Oct  3 14:35:40 2015 >>> www-client/firefox-38.3.0
>        merge time: 36 minutes and 53 seconds.
>
>      Fri Nov  6 09:10:06 2015 >>> www-client/firefox-38.4.0
>        merge time: 38 minutes and 8 seconds.
>
>
> In contrast a year old AMD A10-7850K APU is significantly faster:
>
>      Sat Oct  3 19:40:48 2015 >>> www-client/firefox-38.3.0
>        merge time: 17 minutes and 42 seconds.
>
>      Fri Nov  6 08:41:02 2015 >>> www-client/firefox-38.4.0
>        merge time: 18 minutes and 18 seconds.
>
>
> I would also be interested to see compile times of more modern i7s and FXs, 
> but bear in mind that in single core operations Intel is these days 
> significantly better than AMD.
>
So, I shouldn't prepare for a 8x times faster compile time... :(

Re: [gentoo-user] Better CPU for compiling with gcc

[Alan McKinnon]

On 10/11/2015 20:37, Stanislav Nikolov wrote:
> 
> 
> On 11/10/2015 08:17 PM, Mick wrote:
>> On Tuesday 10 Nov 2015 17:47:08 Stanislav Nikolov wrote:
>>> Dear Gentoo users,
>>> I'm building a new PC. I have a budget of ~$550-$650. No GPU, no special
>>> case (I may use a card box), not even a hdd or ssd. So, as you can see,
>>> it's pretty much "get the best CPU and mobo/ram that are compatible with
>>> it". The problem is, which is the best one. By "best" I mean to compile
>>> shit fast. My laptop with 3rd gen i5 compiles firefox for 40 minutes on
>>> average.
>>>
>>> The most expensive Intel CPU is the skylake i7-6700k. But is it the best?
>>> Is there something from AMD that will perform even better? I can't find
>>> any benchmarks with AMD/Intel CPUs. And how much does the mobo matter?
>>> Will a cheap $30 400W PSU power that thing?
>>>
>>> Thanks
>> I don't (yet) own a i7-6700k, but my 6 year old laptop with (1st generation) 
>> i7 Q720  @1.60GHz takes slightly less than yours:
>>
>>      Sat Oct  3 14:35:40 2015 >>> www-client/firefox-38.3.0
>>        merge time: 36 minutes and 53 seconds.
>>
>>      Fri Nov  6 09:10:06 2015 >>> www-client/firefox-38.4.0
>>        merge time: 38 minutes and 8 seconds.
>>
>>
>> In contrast a year old AMD A10-7850K APU is significantly faster:
>>
>>      Sat Oct  3 19:40:48 2015 >>> www-client/firefox-38.3.0
>>        merge time: 17 minutes and 42 seconds.
>>
>>      Fri Nov  6 08:41:02 2015 >>> www-client/firefox-38.4.0
>>        merge time: 18 minutes and 18 seconds.
>>
>>
>> I would also be interested to see compile times of more modern i7s and FXs, 
>> but bear in mind that in single core operations Intel is these days 
>> significantly better than AMD.
>>
> So, I shouldn't prepare for a 8x times faster compile time... :(
> 



I can't help but think you are approaching this from the wrong perspective.

Why exactly are you using compile times as your sole criterion? Are you
building a compile farm for Ubuntu? Running continuous integration tests
for LibreOffice [on a $600 budget in a cardboard box :-) ]?

Or do you want emerge world to get it over with quicker?

If the latter, you better rethink your priorities. In computing terms,
compilation is a rare event; launching apps is a common event; and
writing to the disk happens all the time. Optimize for the common case.

A CPU never works in isolation, it is always part of a much larger
system, like disks, RAM and all possible kinds of I/O. The best CPU on
the market plugged into a POS motherboard will perform on emerge world
like a piece of shit - it will follow the weakest link.

If you want to build a compiling machine, buy the best collection of
stuff that works together well and still fits the budget. If you want a
machine that you can use and be happy with, ignoree the temptation to
must have the biggest baddest fastest CU (you will never get to use all
that big bad fast) and invest rather in gobs of RAM and an SSD. Remember
that apps are launched many times more than they are compiled. Or put
another way, sacrifice compilation times t get something you can use.



-- 
Alan McKinnon
alan.mckinnon@gmail.com

Re: [gentoo-user] Better CPU for compiling with gcc

[Stanislav Nikolov]

On 11/10/2015 08:55 PM, Alan McKinnon wrote:
> On 10/11/2015 20:37, Stanislav Nikolov wrote:
>>
>> On 11/10/2015 08:17 PM, Mick wrote:
>>> On Tuesday 10 Nov 2015 17:47:08 Stanislav Nikolov wrote:
>>>> Dear Gentoo users,
>>>> I'm building a new PC. I have a budget of ~$550-$650. No GPU, no special
>>>> case (I may use a card box), not even a hdd or ssd. So, as you can see,
>>>> it's pretty much "get the best CPU and mobo/ram that are compatible with
>>>> it". The problem is, which is the best one. By "best" I mean to compile
>>>> shit fast. My laptop with 3rd gen i5 compiles firefox for 40 minutes on
>>>> average.
>>>>
>>>> The most expensive Intel CPU is the skylake i7-6700k. But is it the best?
>>>> Is there something from AMD that will perform even better? I can't find
>>>> any benchmarks with AMD/Intel CPUs. And how much does the mobo matter?
>>>> Will a cheap $30 400W PSU power that thing?
>>>>
>>>> Thanks
>>> I don't (yet) own a i7-6700k, but my 6 year old laptop with (1st generation) 
>>> i7 Q720  @1.60GHz takes slightly less than yours:
>>>
>>>      Sat Oct  3 14:35:40 2015 >>> www-client/firefox-38.3.0
>>>        merge time: 36 minutes and 53 seconds.
>>>
>>>      Fri Nov  6 09:10:06 2015 >>> www-client/firefox-38.4.0
>>>        merge time: 38 minutes and 8 seconds.
>>>
>>>
>>> In contrast a year old AMD A10-7850K APU is significantly faster:
>>>
>>>      Sat Oct  3 19:40:48 2015 >>> www-client/firefox-38.3.0
>>>        merge time: 17 minutes and 42 seconds.
>>>
>>>      Fri Nov  6 08:41:02 2015 >>> www-client/firefox-38.4.0
>>>        merge time: 18 minutes and 18 seconds.
>>>
>>>
>>> I would also be interested to see compile times of more modern i7s and FXs, 
>>> but bear in mind that in single core operations Intel is these days 
>>> significantly better than AMD.
>>>
>> So, I shouldn't prepare for a 8x times faster compile time... :(
>>
>
>
> I can't help but think you are approaching this from the wrong perspective.
>
> Why exactly are you using compile times as your sole criterion? Are you
> building a compile farm for Ubuntu? Running continuous integration tests
> for LibreOffice [on a $600 budget in a cardboard box :-) ]?
>
> Or do you want emerge world to get it over with quicker?
>
> If the latter, you better rethink your priorities. In computing terms,
> compilation is a rare event; launching apps is a common event; and
> writing to the disk happens all the time. Optimize for the common case.
>
> A CPU never works in isolation, it is always part of a much larger
> system, like disks, RAM and all possible kinds of I/O. The best CPU on
> the market plugged into a POS motherboard will perform on emerge world
> like a piece of shit - it will follow the weakest link.
>
> If you want to build a compiling machine, buy the best collection of
> stuff that works together well and still fits the budget. If you want a
> machine that you can use and be happy with, ignoree the temptation to
> must have the biggest baddest fastest CU (you will never get to use all
> that big bad fast) and invest rather in gobs of RAM and an SSD. Remember
> that apps are launched many times more than they are compiled. Or put
> another way, sacrifice compilation times t get something you can use.

8GB of RAM are waaay more than I use daily (several firefox tabs, nvim = 2Gb max), I have a pretty fast SSD too. Even buying 8GB RAM and a brand new SSD, I have > $450 left. Can I buy a AMD CPU that will get the job done faster than 6700k and/or cheaper?

Re: [gentoo-user] Better CPU for compiling with gcc

[Alec Ten Harmsel]

On 2015-11-10 14:07, Stanislav Nikolov wrote:
>
> On 11/10/2015 08:55 PM, Alan McKinnon wrote:
>> On 10/11/2015 20:37, Stanislav Nikolov wrote:
>>> On 11/10/2015 08:17 PM, Mick wrote:
>>>> On Tuesday 10 Nov 2015 17:47:08 Stanislav Nikolov wrote:
>>>>> Dear Gentoo users,
>>>>> I'm building a new PC. I have a budget of ~$550-$650.
>>>>>
>>>>> <snip>
>>>>>
>>>>> The most expensive Intel CPU is the skylake i7-6700k.
>>>>>
>>>>> Thanks
>>>>
>>
>> I can't help but think you are approaching this from the wrong perspective.
>>
>> Why exactly are you using compile times as your sole criterion? Are you
>> building a compile farm for Ubuntu? Running continuous integration tests
>> for LibreOffice [on a $600 budget in a cardboard box :-) ]?
>>
>> Or do you want emerge world to get it over with quicker?
>>
>> If the latter, you better rethink your priorities. In computing terms,
>> compilation is a rare event; launching apps is a common event; and
>> writing to the disk happens all the time. Optimize for the common case.

In addition, upgrades are something that can be done overnight, or 
really any time you are not using the machine.

>>
>> A CPU never works in isolation, it is always part of a much larger
>> system, like disks, RAM and all possible kinds of I/O. The best CPU on
>> the market plugged into a POS motherboard will perform on emerge world
>> like a piece of shit - it will follow the weakest link.

This; I have an i7-3930K, which has 6 physical cores at 3.8GHz. I also 
have 32GB of RAM and an SSD. There was a large speedup[1] moving 
portage's workdir from SSD to tmpfs. Compiling is a really balanced 
workload, stressing the disk (multiple small reads), memory, and CPU. 
For fast compilation, emphasize RAM first (compile in tmpfs if 
possible), then CPU, then disk. Like Alan said, though, you should 
really optimize for the average case on not worry about the speed of 
compiling stuff.

Alec

1. It was a long time ago so I don't remember the exact numbers, but my 
firefox compiling time went from ~15 minutes to ~10 minutes after 
switching from SSD to tmpfs for portage's workdir.

Re: [gentoo-user] Better CPU for compiling with gcc

[Alan McKinnon]

On 10/11/2015 21:07, Stanislav Nikolov wrote:
> 
> 
> On 11/10/2015 08:55 PM, Alan McKinnon wrote:
>> On 10/11/2015 20:37, Stanislav Nikolov wrote:
>>>
>>> On 11/10/2015 08:17 PM, Mick wrote:
>>>> On Tuesday 10 Nov 2015 17:47:08 Stanislav Nikolov wrote:
>>>>> Dear Gentoo users,
>>>>> I'm building a new PC. I have a budget of ~$550-$650. No GPU, no special
>>>>> case (I may use a card box), not even a hdd or ssd. So, as you can see,
>>>>> it's pretty much "get the best CPU and mobo/ram that are compatible with
>>>>> it". The problem is, which is the best one. By "best" I mean to compile
>>>>> shit fast. My laptop with 3rd gen i5 compiles firefox for 40 minutes on
>>>>> average.
>>>>>
>>>>> The most expensive Intel CPU is the skylake i7-6700k. But is it the best?
>>>>> Is there something from AMD that will perform even better? I can't find
>>>>> any benchmarks with AMD/Intel CPUs. And how much does the mobo matter?
>>>>> Will a cheap $30 400W PSU power that thing?
>>>>>
>>>>> Thanks
>>>> I don't (yet) own a i7-6700k, but my 6 year old laptop with (1st generation) 
>>>> i7 Q720  @1.60GHz takes slightly less than yours:
>>>>
>>>>      Sat Oct  3 14:35:40 2015 >>> www-client/firefox-38.3.0
>>>>        merge time: 36 minutes and 53 seconds.
>>>>
>>>>      Fri Nov  6 09:10:06 2015 >>> www-client/firefox-38.4.0
>>>>        merge time: 38 minutes and 8 seconds.
>>>>
>>>>
>>>> In contrast a year old AMD A10-7850K APU is significantly faster:
>>>>
>>>>      Sat Oct  3 19:40:48 2015 >>> www-client/firefox-38.3.0
>>>>        merge time: 17 minutes and 42 seconds.
>>>>
>>>>      Fri Nov  6 08:41:02 2015 >>> www-client/firefox-38.4.0
>>>>        merge time: 18 minutes and 18 seconds.
>>>>
>>>>
>>>> I would also be interested to see compile times of more modern i7s and FXs, 
>>>> but bear in mind that in single core operations Intel is these days 
>>>> significantly better than AMD.
>>>>
>>> So, I shouldn't prepare for a 8x times faster compile time... :(
>>>
>>
>>
>> I can't help but think you are approaching this from the wrong perspective.
>>
>> Why exactly are you using compile times as your sole criterion? Are you
>> building a compile farm for Ubuntu? Running continuous integration tests
>> for LibreOffice [on a $600 budget in a cardboard box :-) ]?
>>
>> Or do you want emerge world to get it over with quicker?
>>
>> If the latter, you better rethink your priorities. In computing terms,
>> compilation is a rare event; launching apps is a common event; and
>> writing to the disk happens all the time. Optimize for the common case.
>>
>> A CPU never works in isolation, it is always part of a much larger
>> system, like disks, RAM and all possible kinds of I/O. The best CPU on
>> the market plugged into a POS motherboard will perform on emerge world
>> like a piece of shit - it will follow the weakest link.
>>
>> If you want to build a compiling machine, buy the best collection of
>> stuff that works together well and still fits the budget. If you want a
>> machine that you can use and be happy with, ignoree the temptation to
>> must have the biggest baddest fastest CU (you will never get to use all
>> that big bad fast) and invest rather in gobs of RAM and an SSD. Remember
>> that apps are launched many times more than they are compiled. Or put
>> another way, sacrifice compilation times t get something you can use.
> 
> 8GB of RAM are waaay more than I use daily (several firefox tabs, nvim = 2Gb max), I have a pretty fast SSD too. Even buying 8GB RAM and a brand new SSD, I have > $450 left. Can I buy a AMD CPU that will get the job done faster than 6700k and/or cheaper?
> 


That changes things. It wasn't obvious you already had RAM & SSD & stuff.

I'd first make sure I have a decent PSU - none of that crap puny
el-cheapo $300 shit (search list archives for 1000s of posts about dodgy
PSUs). Then split the difference between 8G RAM, a good CPU and an
excellent motherboard. You will use that extra RAM, and a motherboard
that ties all the bits together properly is much more cost-effective
than raw CPU grunt alone.

-- 
Alan McKinnon
alan.mckinnon@gmail.com

Re: [gentoo-user] Better CPU for compiling with gcc

[Dale]

Alan McKinnon wrote:
> On 10/11/2015 21:07, Stanislav Nikolov wrote:
>>
>> 8GB of RAM are waaay more than I use daily (several firefox tabs, nvim = 2Gb max), I have a pretty fast SSD too. Even buying 8GB RAM and a brand new SSD, I have > $450 left. Can I buy a AMD CPU that will get the job done faster than 6700k and/or cheaper?
>>
>
> That changes things. It wasn't obvious you already had RAM & SSD & stuff.
>
> I'd first make sure I have a decent PSU - none of that crap puny
> el-cheapo $300 shit (search list archives for 1000s of posts about dodgy
> PSUs). Then split the difference between 8G RAM, a good CPU and an
> excellent motherboard. You will use that extra RAM, and a motherboard
> that ties all the bits together properly is much more cost-effective
> than raw CPU grunt alone.
>


If he needs a guide to at least increase the odds of getting a good P/S,
this may help.

http://www.jonnyguru.com/modules.php?name=NDReviews&op=Review_Cat&recatnum=13


I been reading their reviews for a few years.  They are pretty tough. 
To be honest, if I picked out one that rated 8 on their scale, that
would likely be a good P/S for me.  You get into the 9's and it should
be a really good one.  Short of lightening, it would be the last thing
I'd expect trouble from.  They torture them pretty well.  Should be the
worst a P/S should ever see, example, air conditioner goes out and its
really warm that day.   Also, they take them apart so you can see what
is inside them, good brand of caps for example.  Still, they include the
quality of the build and parts in their scoring.  If a company skimps on
that, they deduct points. 

Honestly tho, the P/S is a critical part.  If it fails, it can wreak all
kinds of havoc.  I've seen P/Ss go out and take a mobo, hard drive or
something else out with it.  After all, pretty much everythign plugs
into power somehow. 

Hope that helps. 

Dale

:-)  :-) 

P. S.  Makes me want to upgrade my CPU to a 8 core now.  I need a hard
drive first tho.  ;-)

Re: [gentoo-user] Better CPU for compiling with gcc

[Mick]

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On Tuesday 10 Nov 2015 19:41:46 Dale wrote:
> Alan McKinnon wrote:
> > On 10/11/2015 21:07, Stanislav Nikolov wrote:
> >> 8GB of RAM are waaay more than I use daily (several firefox tabs, nvim =
> >> 2Gb max), I have a pretty fast SSD too. Even buying 8GB RAM and a brand
> >> new SSD, I have > $450 left. Can I buy a AMD CPU that will get the job
> >> done faster than 6700k and/or cheaper?
> > 
> > That changes things. It wasn't obvious you already had RAM & SSD & stuff.
> > 
> > I'd first make sure I have a decent PSU - none of that crap puny
> > el-cheapo $300 shit (search list archives for 1000s of posts about dodgy
> > PSUs). Then split the difference between 8G RAM, a good CPU and an
> > excellent motherboard. You will use that extra RAM, and a motherboard
> > that ties all the bits together properly is much more cost-effective
> > than raw CPU grunt alone.
> 
> If he needs a guide to at least increase the odds of getting a good P/S,
> this may help.
> 
> http://www.jonnyguru.com/modules.php?name=NDReviews&op=Review_Cat&recatnum=
> 13
> 
> 
> I been reading their reviews for a few years.  They are pretty tough.
> To be honest, if I picked out one that rated 8 on their scale, that
> would likely be a good P/S for me.  You get into the 9's and it should
> be a really good one.  Short of lightening, it would be the last thing
> I'd expect trouble from.  They torture them pretty well.  Should be the
> worst a P/S should ever see, example, air conditioner goes out and its
> really warm that day.   Also, they take them apart so you can see what
> is inside them, good brand of caps for example.  Still, they include the
> quality of the build and parts in their scoring.  If a company skimps on
> that, they deduct points.
> 
> Honestly tho, the P/S is a critical part.  If it fails, it can wreak all
> kinds of havoc.  I've seen P/Ss go out and take a mobo, hard drive or
> something else out with it.  After all, pretty much everythign plugs
> into power somehow.
> 
> Hope that helps.
> 
> Dale
> 
> :-)  :-)
> 
> P. S.  Makes me want to upgrade my CPU to a 8 core now.  I need a hard
> drive first tho.  ;-)


Yes, a good quality PSU will safeguard your components and your data.  Buy 
something with Japanese capacitors.

BTW, let me correct earlier numbers .... My i7 timings are from a conventional 
emerge of firefox with /var/tmp/portage on a spinning drive.  The laptop does 
not have enough memory to emerge FF on a tmpfs.  :p

The AMD emerge timings was derived on a 2400MHz tmpfs.  So this was somewhat 
an apples and oranges comparison.  Apologies for a bum steer.  I wouldn't be 
surprised if the latest skylake i7s on some Ripjaws DDR4 tmpfs wasn't able to 
emerge it closer to 10 minutes.  That would be quite an achievement compared 
to your current PC.

-- 
Regards,
Mick

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