From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lists.gentoo.org (pigeon.gentoo.org [208.92.234.80]) by finch.gentoo.org (Postfix) with ESMTP id B408D1384B4 for ; Tue, 10 Nov 2015 19:25:15 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id A424721C067; Tue, 10 Nov 2015 19:25:05 +0000 (UTC) Received: from mail-wm0-f42.google.com (mail-wm0-f42.google.com [74.125.82.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by pigeon.gentoo.org (Postfix) with ESMTPS id 6F14721C020 for ; Tue, 10 Nov 2015 19:24:59 +0000 (UTC) Received: by wmec201 with SMTP id c201so16849733wme.1 for ; Tue, 10 Nov 2015 11:24:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-type:content-transfer-encoding; bh=2QozKojZnhdfnpwUYal3Ed1KrWlesCJxQm+kQNjK1Ew=; b=igb87sB0Ahr3q9APAPXCmn+LfvTIxZOcGziS+ld3xRSn79ljYGvQSX911R3gTsHeMV uXnZ6vrpY5bqMqqmK54C7af09Cla1ALaIRC1nKaN5wAXrijb7YFQI2txHmCH7rhtQtX+ JJScpy0T6mQsilfupVQk/wLM4EZfePcIrhSGxLL3bEA4YA2xDE5/Tr9tP0WaYgK/DMcs XZoW1rC/Bsp4tWxW89pIxcDt2vRXIlkfbKTKzExxTQu1mTYrZAOcyl4vYfijPcFpCo93 mcPlgON74TGrhi++unl6MlV2S54naWDlgdtdTGjfNiTfeet4zkU8VWyr2jahektqfUme PrDw== X-Received: by 10.195.11.129 with SMTP id ei1mr5567858wjd.129.1447183498270; Tue, 10 Nov 2015 11:24:58 -0800 (PST) Received: from [172.20.0.40] ([165.255.82.143]) by smtp.googlemail.com with ESMTPSA id hk1sm5098020wjb.6.2015.11.10.11.24.56 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 10 Nov 2015 11:24:57 -0800 (PST) Subject: Re: [gentoo-user] Better CPU for compiling with gcc To: gentoo-user@lists.gentoo.org References: <56422D9C.6060001@gmail.com> <201511101817.35016.michaelkintzios@gmail.com> <56423958.2030802@gmail.com> <56423DB7.4030605@gmail.com> <5642406E.2080808@gmail.com> From: Alan McKinnon Message-ID: <5642444D.9050205@gmail.com> Date: Tue, 10 Nov 2015 21:23:57 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 In-Reply-To: <5642406E.2080808@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Archives-Salt: c65e710d-5d65-4930-8fec-4bf3dbb48903 X-Archives-Hash: 433848675c449c1ec81f715b1e56e78c 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