Re: which program can test cpu speed
On Fri, Oct 26, 2018 at 09:16:47PM +0300, Reco wrote: As far as I remember, the bogomips number has consistently been twice the current clock frequency on any x86 PCU I have ever run Linux on. Either your math is off, or they've changed it. $ lscpu | egrep '(Vendor|MHz|MIPS)' # This PC Vendor ID: GenuineIntel CPU MHz: 1599.975 CPU max MHz: 3800. CPU min MHz: 1600. BogoMIPS: 6800.59 Who knows what "this pc" is. In this case bogomips is a little less than double, may be the system is configured to never exceed 3.4GHz (derated) or may be the difference between core and turbo or who knows what else. Would help to see CPU model. (In future, "Model name" is much more usefule than "Vendor".) $ lscpu | egrep '(Vendor|MHz|MIPS)' # Certain VPS Vendor ID: GenuineIntel CPU MHz: 2099.996 BogoMIPS: 4199.99 About double. And, $ lscpu | egrep '(Vendor|MHz|MIPS)' # Xeon X5675 Vendor ID: GenuineIntel CPU MHz: 1600.000 BogoMIPS: 6117.70 x5675 is a 3.06GHz CPU that turbos to 3.46GHz, so bogomips is indeed about double the core frequency here. Older CPUs don't show min/max in lscpu output, only current frequency. I spot checked a few systems here, found bogomips consistently about 2x max clock on skylake, haswell, xen+, silvermont, braswell and a couple of others. Heck, even the oldest thing I have that boots (a 200MHz pentium MMX) has a bogomips of 399.77 -- about double the MHz. The pentium pro family (+ ii & iii) got roughly the same bogomips as MHz. You have to go all the way back to the original pentiums, 486s, and 386s before you see major differences in the multipliers between CPUs. Anyway, the point remains--this is not useful as a benchmark.
Re: which program can test cpu speed
On Fri, Oct 26, 2018 at 01:47:19PM -0500, David Wright wrote: On Fri 26 Oct 2018 at 11:04:48 (-0400), Michael Stone wrote: FWIW, even the kernel doesn't use naive busy loops anymore on newer hardware. (TSC or MWAIT is used, depending on what the processor supports.) I've programmed a "busy loop" in the past and found that linux bogomips tracked the loop speed quite closely on a variety of machines from 486DX to 650MHz Pentium III (Coppermine). Nothing multiprocessor. When I say busy loop, I mean a loop like FOR J=1 TO T X=X+1 NEXT J where X is floating point and the language is an HP Basic clone on MSDOS. That's basically all bogomips is: " test %0,%0 \n" " jz 3f \n" " jmp 1f \n" ".align 16 \n" "1:jmp 2f \n" ".align 16 \n" "2:dec %0 \n" " jnz 2b \n" "3:dec %0 \n" in a loop. (From https://github.com/torvalds/linux/blob/master/arch/x86/lib/delay.c) (Note that other architectures are completely different and don't use the x86 assembly--one more way the bogomips numbers are meaningless. :) ) For a given CPU family there's a de-facto multiplier (essentially, how many instructions can be issued per cycle) and then within that family bogomips is directly proportional to clock speed. None of that works particularly well in the face of CPUs that change speed, and it's not particularly efficient given current desires to minimizing power consumption. So, current CPUs use the TSC (which, again for current CPUs, increments at a constant rate regardless of reduced clock speeds in power saving modes) possibly in concert with MWAIT (which lets the CPU idle for a bit to save power). In those cases the loop frequency calibration is just determining how the TSC counter relates to wall clock time, and has nothing at all to do with CPU performance--even the minimal "how fast can the CPU run these 5 instructions" 'benchmark' of classic bogomips.
Re: which program can test cpu speed
On Fri 26 Oct 2018 at 11:04:48 (-0400), Michael Stone wrote: > On Fri, Oct 26, 2018 at 05:34:26PM +0300, Reco wrote: > > On Fri, Oct 26, 2018 at 09:59:16AM -0400, Michael Stone wrote: > > > On Fri, Oct 26, 2018 at 08:57:29AM +0300, Reco wrote: > > > > Why would you need a *program* to do that then you have Linux kernel > > > > already? > > > > > > > > grep bogomips /proc/cpuinfo > > > > > > Anyone reading that advice: ignore it. You cannot use bogomips to > > > meaningfully compare processors. > > > > The reason being? > > As it says in the link you posted, "It is not usable for performance > comparisons among different CPUs". > > > The kernel uses it just fine for the clock calibration. > > I suppose if you want to use the system exclusively for busy loops, > you can use the bogomips number to see which cpu will wait the fastest > and choose based on that. > > FWIW, even the kernel doesn't use naive busy loops anymore on newer > hardware. (TSC or MWAIT is used, depending on what the processor > supports.) I've programmed a "busy loop" in the past and found that linux bogomips tracked the loop speed quite closely on a variety of machines from 486DX to 650MHz Pentium III (Coppermine). Nothing multiprocessor. When I say busy loop, I mean a loop like FOR J=1 TO T X=X+1 NEXT J where X is floating point and the language is an HP Basic clone on MSDOS. Cheers, David.
Re: which program can test cpu speed
On Fri, Oct 26, 2018 at 02:02:06PM -0400, Michael Stone wrote: On Fri, Oct 26, 2018 at 05:19:58PM +, Long Wind wrote: is there any general-purpose testing utility? i remember in early days some program for DOS can report benchmark, (maybe made by nordon?) . and intel 486 always seems faster than 386. Try something like http://www.cpu-world.com/Compare/803/AMD_Athlon_64_X2_3800+_(Socket_AM2__35W__IAA)_vs_Intel_Pentium_D_820.html (guessing on the cpus, you were a bit vague) Another one is https://www.cpubenchmark.net/compare/AMD-Athlon-64-X2-Dual-Core-3800+-vs-Intel-Pentium-D-915/77vs1126 If you really want to run something, apt-get install lmbench. You can also take a look at http://linux-bench.com/
Re: which program can test cpu speed
On Fri, Oct 26, 2018 at 07:51:16PM +0200, Pascal Hambourg wrote: > Le 26/10/2018 à 16:34, Reco a écrit : > > > > On Fri, Oct 26, 2018 at 09:59:16AM -0400, Michael Stone wrote: > > > On Fri, Oct 26, 2018 at 08:57:29AM +0300, Reco wrote: > > > > > > > > grep bogomips /proc/cpuinfo > > > > > > Anyone reading that advice: ignore it. You cannot use bogomips to > > > meaningfully compare processors. > > > > The reason being? > > The kernel uses it just fine for the clock calibration. > > As far as I remember, the bogomips number has consistently been twice the > current clock frequency on any x86 PCU I have ever run Linux on. Either your math is off, or they've changed it. $ lscpu | egrep '(Vendor|MHz|MIPS)' # This PC Vendor ID: GenuineIntel CPU MHz: 1599.975 CPU max MHz: 3800. CPU min MHz: 1600. BogoMIPS: 6800.59 $ lscpu | egrep '(Vendor|MHz|MIPS)' # Certain VPS Vendor ID: GenuineIntel CPU MHz: 2099.996 BogoMIPS: 4199.99 And, $ lscpu | egrep '(Vendor|MHz|MIPS)' # Xeon X5675 Vendor ID: GenuineIntel CPU MHz: 1600.000 BogoMIPS: 6117.70 > How can you measure and compare processor performance from the mere clock > frequency ? That's I agree with. REco
Re: which program can test cpu speed
On Fri, Oct 26, 2018 at 05:19:58PM +, Long Wind wrote: is there any general-purpose testing utility? i remember in early days some program for DOS can report benchmark, (maybe made by nordon?) . and intel 486 always seems faster than 386. Try something like http://www.cpu-world.com/Compare/803/AMD_Athlon_64_X2_3800+_(Socket_AM2__35W__IAA)_vs_Intel_Pentium_D_820.html (guessing on the cpus, you were a bit vague) The performance of a given system depends on the task. Some systems are better at single-threaded integer calculations, some have more cores so they're better in a multitasking environment, some have better floating point optimizations, some have more cache and therefore perform better when code jumps all over the place, etc. You need to benchmark the systems for whatever task YOU actually care about. Whatever program you're using that makes you think "gosh, I really wish this system could be faster" -- that's the one you use to benchmark. It could be compiling the Linux kernel, or transcoding video and audio, or calculating prime factors of large numbers, or first-person shooter video games, or whatever it is that you do. The above was good advice. There's no such thing as "a general benchmark"; there are benchmarks to test integer performance, benchmarks to test floating point performance, benchmarks to test graphics, benchmarks to test storage, etc. If you don't have any specific task that you want to test, then suffice it to say that both systems are equally slow by modern standards. I'd expect that the AMD CPU is a bit better/has more functionality, but you probably won't be able to tell the difference. The graphics on a 10 year old system are likely to be a bigger issue than the CPU. You'd probably get dramatically better results by replacing whatever the hard drive is with an SSD rather than by agonizing over the CPU selection.
Re: which program can test cpu speed
Le 26/10/2018 à 16:34, Reco a écrit : On Fri, Oct 26, 2018 at 09:59:16AM -0400, Michael Stone wrote: On Fri, Oct 26, 2018 at 08:57:29AM +0300, Reco wrote: grep bogomips /proc/cpuinfo Anyone reading that advice: ignore it. You cannot use bogomips to meaningfully compare processors. The reason being? The kernel uses it just fine for the clock calibration. As far as I remember, the bogomips number has consistently been twice the current clock frequency on any x86 PCU I have ever run Linux on. How can you measure and compare processor performance from the mere clock frequency ?
Re: which program can test cpu speed
Thank Greg! is there any general-purpose testing utility? i remember in early days some program for DOS can report benchmark, (maybe made by nordon?) . and intel 486 always seems faster than 386. On Friday, October 26, 2018 8:40 PM, Greg Wooledge wrote: On Fri, Oct 26, 2018 at 03:05:36AM +, Long Wind wrote: > any package that test cpu/system speed and report benchmark? > i have 2 old pc: intel pentium D 2.8 G and amd athlon 64 3800i bought them > from 2nd hand dealers for about same priceso i think they're about same speed The performance of a given system depends on the task. Some systems are better at single-threaded integer calculations, some have more cores so they're better in a multitasking environment, some have better floating point optimizations, some have more cache and therefore perform better when code jumps all over the place, etc. You need to benchmark the systems for whatever task YOU actually care about. Whatever program you're using that makes you think "gosh, I really wish this system could be faster" -- that's the one you use to benchmark. It could be compiling the Linux kernel, or transcoding video and audio, or calculating prime factors of large numbers, or first-person shooter video games, or whatever it is that you do.
Re: which program can test cpu speed
On Fri, Oct 26, 2018 at 05:34:26PM +0300, Reco wrote: On Fri, Oct 26, 2018 at 09:59:16AM -0400, Michael Stone wrote: On Fri, Oct 26, 2018 at 08:57:29AM +0300, Reco wrote: > Why would you need a *program* to do that then you have Linux kernel > already? > > grep bogomips /proc/cpuinfo Anyone reading that advice: ignore it. You cannot use bogomips to meaningfully compare processors. The reason being? As it says in the link you posted, "It is not usable for performance comparisons among different CPUs". The kernel uses it just fine for the clock calibration. I suppose if you want to use the system exclusively for busy loops, you can use the bogomips number to see which cpu will wait the fastest and choose based on that. FWIW, even the kernel doesn't use naive busy loops anymore on newer hardware. (TSC or MWAIT is used, depending on what the processor supports.) Mike Stone
Re: which program can test cpu speed
Hi. On Fri, Oct 26, 2018 at 03:21:41PM +0100, mick crane wrote: > On 2018-10-26 06:57, Reco wrote: > > Hi. > > > > On Fri, Oct 26, 2018 at 03:05:36AM +, Long Wind wrote: > > > any package that test cpu/system speed and report benchmark? > > > i have 2 old pc: intel pentium D 2.8 G and amd athlon 64 3800i bought > > > them from 2nd hand dealers for about same priceso i think > > > they're about same speed > > > > Why would you need a *program* to do that then you have Linux kernel > > already? > > > > grep bogomips /proc/cpuinfo > > > > Reco > > Just saying I really appreciate the responses you are giving. > Not things that particularly trouble me at present but learning stuff with > each one. I always appreciate kind words, good sir. Thank you. Reco
Re: which program can test cpu speed
Hi. On Fri, Oct 26, 2018 at 09:59:16AM -0400, Michael Stone wrote: > On Fri, Oct 26, 2018 at 08:57:29AM +0300, Reco wrote: > > Why would you need a *program* to do that then you have Linux kernel > > already? > > > > grep bogomips /proc/cpuinfo > > Anyone reading that advice: ignore it. You cannot use bogomips to > meaningfully compare processors. The reason being? The kernel uses it just fine for the clock calibration. Reco
Re: which program can test cpu speed
On 2018-10-26 06:57, Reco wrote: Hi. On Fri, Oct 26, 2018 at 03:05:36AM +, Long Wind wrote: any package that test cpu/system speed and report benchmark? i have 2 old pc: intel pentium D 2.8 G and amd athlon 64 3800i bought them from 2nd hand dealers for about same priceso i think they're about same speed Why would you need a *program* to do that then you have Linux kernel already? grep bogomips /proc/cpuinfo Reco Just saying I really appreciate the responses you are giving. Not things that particularly trouble me at present but learning stuff with each one. thanks mick -- Key ID4BFEBB31
Re: which program can test cpu speed
On Fri, Oct 26, 2018 at 08:57:29AM +0300, Reco wrote: Why would you need a *program* to do that then you have Linux kernel already? grep bogomips /proc/cpuinfo Anyone reading that advice: ignore it. You cannot use bogomips to meaningfully compare processors. Mike Stone
Re: which program can test cpu speed
On Fri, Oct 26, 2018 at 03:05:36AM +, Long Wind wrote: > any package that test cpu/system speed and report benchmark? > i have 2 old pc: intel pentium D 2.8 G and amd athlon 64 3800i bought them > from 2nd hand dealers for about same priceso i think they're about same speed The performance of a given system depends on the task. Some systems are better at single-threaded integer calculations, some have more cores so they're better in a multitasking environment, some have better floating point optimizations, some have more cache and therefore perform better when code jumps all over the place, etc. You need to benchmark the systems for whatever task YOU actually care about. Whatever program you're using that makes you think "gosh, I really wish this system could be faster" -- that's the one you use to benchmark. It could be compiling the Linux kernel, or transcoding video and audio, or calculating prime factors of large numbers, or first-person shooter video games, or whatever it is that you do.
Re: which program can test cpu speed
On Fri, 26 Oct 2018 11:54:26 +0300 Reco wrote: > Hi. > > On Fri, Oct 26, 2018 at 10:42:53AM +0200, arne wrote: > > On Fri, 26 Oct 2018 11:26:13 +0300 > > Reco wrote: > > > > > Hi. > > > > > > On Fri, Oct 26, 2018 at 08:17:31AM +, Long Wind wrote: > > > > Thank Reco! > > > > > > You're welcome. > > > > > > > > > > intel get higher mark than amd > > > > > > That's expected. You need raw CPU power - you buy Intel. > > > > > > > You need power buy AMD threadripper: 64 threads > > If I ever need many threads, I'll buy Xeon. You can compare: https://img.purch.com/r/711x457/aHR0cDovL21lZGlhLmJlc3RvZm1pY3JvLmNvbS9ILzAvNzkxMTcyL29yaWdpbmFsL2ltYWdlMDA0LnBuZw== > If I ever need enormous amount of threads, I'll buy UltraSPARC. > If I ever need good single CPU - there's IBM's Power for that. > If I need low TDP - there are ARM and MIPS. > > AMD just does not fit anywhere. > > Reco >
Re: which program can test cpu speed
Hi. On Fri, Oct 26, 2018 at 10:42:53AM +0200, arne wrote: > On Fri, 26 Oct 2018 11:26:13 +0300 > Reco wrote: > > > Hi. > > > > On Fri, Oct 26, 2018 at 08:17:31AM +, Long Wind wrote: > > > Thank Reco! > > > > You're welcome. > > > > > > > intel get higher mark than amd > > > > That's expected. You need raw CPU power - you buy Intel. > > > > You need power buy AMD threadripper: 64 threads If I ever need many threads, I'll buy Xeon. If I ever need enormous amount of threads, I'll buy UltraSPARC. If I ever need good single CPU - there's IBM's Power for that. If I need low TDP - there are ARM and MIPS. AMD just does not fit anywhere. Reco
Re: which program can test cpu speed
On Fri, 26 Oct 2018 11:26:13 +0300 Reco wrote: > Hi. > > On Fri, Oct 26, 2018 at 08:17:31AM +, Long Wind wrote: > > Thank Reco! > > You're welcome. > > > > intel get higher mark than amd > > That's expected. You need raw CPU power - you buy Intel. > You need power buy AMD threadripper: 64 threads
Re: which program can test cpu speed
There is a "perf" package complementing the linux kernel package, for example if the kernel package is linux-image-4.17.0-3-amd64 the perf package is linux-perf-4.17. Also, take a look at this web page http://www.brendangregg.com/FlameGraphs/cpuflamegraphs.html about profiling by Brendan Gregg. Regards, Jörg.
Re: which program can test cpu speed
Hi. On Fri, Oct 26, 2018 at 08:17:31AM +, Long Wind wrote: > Thank Reco! You're welcome. > intel get higher mark than amd That's expected. You need raw CPU power - you buy Intel. > but could you explain a little about your command and bogomips? > i can't find manual about such info. I feel uneasy for doing this, but - [1]. Reco [1] https://en.wikipedia.org/wiki/BogoMips
Re: which program can test cpu speed
Hi. On Fri, Oct 26, 2018 at 03:05:36AM +, Long Wind wrote: > any package that test cpu/system speed and report benchmark? > i have 2 old pc: intel pentium D 2.8 G and amd athlon 64 3800i bought them > from 2nd hand dealers for about same priceso i think they're about same speed Why would you need a *program* to do that then you have Linux kernel already? grep bogomips /proc/cpuinfo Reco
