Forums

LTspice Loafing?

Started by rickman March 9, 2017
On 03/09/2017 06:49 PM, John Larkin wrote:
> On Thu, 9 Mar 2017 18:01:20 -0500, bitrex > <bitrex@de.lete.earthlink.net> wrote: > >> On 03/09/2017 02:33 PM, John Larkin wrote: >>> On Thu, 9 Mar 2017 09:53:26 -0500, Phil Hobbs >>> <pcdhSpamMeSenseless@electrooptical.net> wrote: >>> >>>> On 03/09/2017 05:37 AM, Johann Klammer wrote: >>>>> On 03/09/2017 09:29 AM, rickman wrote: >>>>>> I was running some simulations on LTspice and it is not even using >>>>>> 5% of my CPU. Nothing else is topping it and the entire computer >>>>>> is pretty much at idle. What could be limiting the speed? >>>>>> >>>>>> One of the main reasons I bought a laptop with an i7 processor was >>>>>> to speed simulations. Is this wasted on LTspice or am I doing >>>>>> something wrong? >>>>>> >>>>> I think it saves the waveforms to a file as it goes along >>>>> simulating. Where you the one who complained about your hdd being >>>>> slow in an earlier thread? maybe try running the sim from an ext usb >>>>> stick. if that helps it's definitely the hdd. >>>>> >>>> >>>> I'd start with a ramdisk and see then. USB sticks are glacial compared >>>> with real flash drives. >>>> >>>> Cheers >>>> >>>> Phil Hobbs >>> >>> Try this one. 32 seconds on my new Dell. Runs about 25% CPU. >> >> I get a simulation speed average of about 150uS/sec on my i7-5500U 2.4 >> Ghz laptop/SSD drive combo with the "normal" solver, running on >> Wine/Xubuntu. > > I'm seeing 720 us/s, Win7, newish Dell desktop with 8G ram.
What's the processor? As a "5th gen" low-power i7 the 5500U stacks up pretty poorly against more modern "7th gen" desktop offerings: https://www.cpubenchmark.net/cpu.php?cpu=Intel+Core+i7-5500U+%40+2.40GHz
On Thu, 9 Mar 2017 19:07:21 -0500, bitrex
<bitrex@de.lete.earthlink.net> wrote:

>On 03/09/2017 06:49 PM, John Larkin wrote: >> On Thu, 9 Mar 2017 18:01:20 -0500, bitrex >> <bitrex@de.lete.earthlink.net> wrote: >> >>> On 03/09/2017 02:33 PM, John Larkin wrote: >>>> On Thu, 9 Mar 2017 09:53:26 -0500, Phil Hobbs >>>> <pcdhSpamMeSenseless@electrooptical.net> wrote: >>>> >>>>> On 03/09/2017 05:37 AM, Johann Klammer wrote: >>>>>> On 03/09/2017 09:29 AM, rickman wrote: >>>>>>> I was running some simulations on LTspice and it is not even using >>>>>>> 5% of my CPU. Nothing else is topping it and the entire computer >>>>>>> is pretty much at idle. What could be limiting the speed? >>>>>>> >>>>>>> One of the main reasons I bought a laptop with an i7 processor was >>>>>>> to speed simulations. Is this wasted on LTspice or am I doing >>>>>>> something wrong? >>>>>>> >>>>>> I think it saves the waveforms to a file as it goes along >>>>>> simulating. Where you the one who complained about your hdd being >>>>>> slow in an earlier thread? maybe try running the sim from an ext usb >>>>>> stick. if that helps it's definitely the hdd. >>>>>> >>>>> >>>>> I'd start with a ramdisk and see then. USB sticks are glacial compared >>>>> with real flash drives. >>>>> >>>>> Cheers >>>>> >>>>> Phil Hobbs >>>> >>>> Try this one. 32 seconds on my new Dell. Runs about 25% CPU. >>> >>> I get a simulation speed average of about 150uS/sec on my i7-5500U 2.4 >>> Ghz laptop/SSD drive combo with the "normal" solver, running on >>> Wine/Xubuntu. >> >> I'm seeing 720 us/s, Win7, newish Dell desktop with 8G ram. > >What's the processor?
Xeon E5-1603 v3 2.8 GHz. Whatever that means.
> >As a "5th gen" low-power i7 the 5500U stacks up pretty poorly against >more modern "7th gen" desktop offerings: > >https://www.cpubenchmark.net/cpu.php?cpu=Intel+Core+i7-5500U+%40+2.40GHz
-- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
On 3/9/2017 7:00 PM, Johann Klammer wrote:
> On 03/10/2017 12:09 AM, bitrex wrote: >> >> Having a CPU with a nice fat L1/L2 cache probably helps a lot too - >> my guess is if that whatever set of matrix data structures LTSpice >> uses internally to represent a single stepping iteration's results >> can't fit inside the CPU cache you're kind of fucked, have to head >> out to RAM/disk every time. > > I doubt it. The slow warthogs are typically buried in the OS/GUI code somewhere. > Can you turn off the marching waveforms? maybe it's a GUI thing?
It runs faster if I hide the waveforms. I can minimize the window in fact, and it pops up when done. -- Rick C
On 03/09/2017 07:13 PM, John Larkin wrote:
> Xeon E5-1603 v3 2.8 GHz
Ah, maybe one of the Facebook specials! <http://www.techspot.com/review/1155-affordable-dual-xeon-pc/> They're available refurb on NewEgg for $38, woah. <https://www.newegg.com/Product/Product.aspx?Item=9SIA4GH4R61733&cm_re=Intel_Xeon_E5-1603-_-9SIA4GH4R61733-_-Product>
On Thu, 9 Mar 2017 20:25:42 -0500, bitrex
<bitrex@de.lete.earthlink.net> wrote:

>On 03/09/2017 07:13 PM, John Larkin wrote: >> Xeon E5-1603 v3 2.8 GHz > >Ah, maybe one of the Facebook specials! > ><http://www.techspot.com/review/1155-affordable-dual-xeon-pc/>
Well, it's a Dell box.
> >They're available refurb on NewEgg for $38, woah. > ><https://www.newegg.com/Product/Product.aspx?Item=9SIA4GH4R61733&cm_re=Intel_Xeon_E5-1603-_-9SIA4GH4R61733-_-Product>
Refurbished? -- John Larkin Highland Technology, Inc lunatic fringe electronics
Am 09.03.2017 um 22:42 schrieb Lasse Langwadt Christensen:
> Den torsdag den 9. marts 2017 kl. 21.53.17 UTC+1 skrev John S: >> On 3/9/2017 1:33 PM, John Larkin wrote:
>>> Try this one. 32 seconds on my new Dell. Runs about 25% CPU. >> >> Mine is an i7 and runs about 25% (only one core, apparently) and takes >> about 53 seconds. The computer is about 5 years old. > > 64bit ltspice under wine in ubuntu on ancient i7-965 > > 20 seconds using 12% (1 core out of 8)
LTspice 4: Linux, virtual Win7 machine VMware Workstation 12: 42 sec same machine in a Linux window LTspice4 with wine under Linux: 22 sec Machine is a Dell Precision "portable Workstation" 3.5 years old. "portable" has to be taken with a grain of salt. 240W power supply. I have no idea which run was on which CPU. The CPUs all run at pretty different speed. regards, Gerhard system description: gerhard@precision:~$ inxi -CDb System: Host: precision Kernel: 4.4.0-62-generic x86_64 (64 bit) Desktop: Cinnamon 2.8.8 Distro: Linux Mint 17.3 Rosa Machine: System: Dell product: Precision M6600 v: 01 Mobo: Dell model: 04YY4M v: A00 Bios: Dell v: A15 date: 09/27/2013 CPU: Quad core Intel Core i7-2820QM (-HT-MCP-) cache: 8192 KB clock speeds: max: 3400 MHz 1: 983 MHz 2: 1281 MHz 3: 1301 MHz 4: 1096 MHz 5: 1564 MHz 6: 1029 MHz 7: 1119 MHz 8: 868 MHz Graphics: Card: NVIDIA GF104GLM [Quadro 4000M] Display Server: X.Org 1.15.1 drivers: nvidia (unloaded: fbdev,vesa,nouveau) Resolution: 1920x1080@60.0hz, 2560x1440@60.0hz GLX Renderer: Quadro 4000M/PCIe/SSE2 GLX Version: 4.5.0 NVIDIA 367.57 Network: Card-1: Intel 82579LM Gigabit Network Connection driver: e1000e Card-2: Intel Centrino Ultimate-N 6300 driver: iwlwifi Drives: HDD Total Size: 1536.3GB (74.0% used) ID-1: /dev/sda model: Samsung_SSD_850 size: 1024.2GB ID-2: /dev/sdb model: SAMSUNG_SSD_830 size: 512.1GB Info: Processes: 268 Uptime: 13:11 Memory: 2589.1/16003.5MB Client: Shell (bash) inxi: 2.2.28
On 3/9/2017 2:33 PM, John Larkin wrote:
> On Thu, 9 Mar 2017 09:53:26 -0500, Phil Hobbs > <pcdhSpamMeSenseless@electrooptical.net> wrote: > >> On 03/09/2017 05:37 AM, Johann Klammer wrote: >>> On 03/09/2017 09:29 AM, rickman wrote: >>>> I was running some simulations on LTspice and it is not even using >>>> 5% of my CPU. Nothing else is topping it and the entire computer >>>> is pretty much at idle. What could be limiting the speed? >>>> >>>> One of the main reasons I bought a laptop with an i7 processor was >>>> to speed simulations. Is this wasted on LTspice or am I doing >>>> something wrong? >>>> >>> I think it saves the waveforms to a file as it goes along >>> simulating. Where you the one who complained about your hdd being >>> slow in an earlier thread? maybe try running the sim from an ext usb >>> stick. if that helps it's definitely the hdd. >>> >> I'd start with a ramdisk and see then. USB sticks are glacial compared >> with real flash drives. >> >> Cheers >> >> Phil Hobbs > > Try this one. 32 seconds on my new Dell. Runs about 25% CPU.
Less than 15 sec on an HP flaptop (ZBook G3 i7...) with 12% of one cpu. Slower and busier with a plot updating. -- Grizzly H.
John Larkin <jjlarkinxyxy@highlandtechnology.com> writes:

> On Thu, 9 Mar 2017 09:53:26 -0500, Phil Hobbs > <pcdhSpamMeSenseless@electrooptical.net> wrote: > >>On 03/09/2017 05:37 AM, Johann Klammer wrote: >>> On 03/09/2017 09:29 AM, rickman wrote: >>>> I was running some simulations on LTspice and it is not even using >>>> 5% of my CPU. Nothing else is topping it and the entire computer >>>> is pretty much at idle. What could be limiting the speed? >>>> >>>> One of the main reasons I bought a laptop with an i7 processor was >>>> to speed simulations. Is this wasted on LTspice or am I doing >>>> something wrong? >>>> >>> I think it saves the waveforms to a file as it goes along >>> simulating. Where you the one who complained about your hdd being >>> slow in an earlier thread? maybe try running the sim from an ext usb >>> stick. if that helps it's definitely the hdd. >>> >> >>I'd start with a ramdisk and see then. USB sticks are glacial compared >>with real flash drives. >> >>Cheers >> >>Phil Hobbs > > Try this one. 32 seconds on my new Dell. Runs about 25% CPU.
20 seconds on my old laptop. On a linux VM! -- John Devereux
"Jim Thompson"  wrote in message 
news:3eq3ccdrdovi1gthst100761vq3bmi0o9j@4ax.com...

>> > >> > Try this one. 32 seconds on my new Dell. Runs about 25% CPU. >> >> Mine is an i7 and runs about 25% (only one core, apparently) and takes >> about 53 seconds. The computer is about 5 years old. > >64bit ltspice under wine in ubuntu on ancient i7-965 > >20 seconds using 12% (1 core out of 8)
>Put LTspice to a test, load a device-level circuit, select >Solver=Alternate and the proper tight solution limits and watch it >crawl, or more likely... hang.
What I will say, is that I have a behavioural modelled SMPS in SS that runs to settling in around 7 secs on my i7 Novatech laptop, so despite LTSpice being 3 times faster than any other Windows spice, who cares if its GUI is shit :-) -- Kevin Aylward http://www.anasoft.co.uk - SuperSpice http://www.kevinaylward.co.uk/ee/index.html
On Fri, 10 Mar 2017 04:51:03 +0100, Gerhard Hoffmann
<ghf@hoffmann-hochfrequenz.de> wrote:

>Am 09.03.2017 um 22:42 schrieb Lasse Langwadt Christensen: >> Den torsdag den 9. marts 2017 kl. 21.53.17 UTC+1 skrev John S: >>> On 3/9/2017 1:33 PM, John Larkin wrote: > >>>> Try this one. 32 seconds on my new Dell. Runs about 25% CPU. >>> >>> Mine is an i7 and runs about 25% (only one core, apparently) and takes >>> about 53 seconds. The computer is about 5 years old. >> >> 64bit ltspice under wine in ubuntu on ancient i7-965 >> >> 20 seconds using 12% (1 core out of 8) > >LTspice 4: Linux, virtual Win7 machine VMware Workstation 12: 42 sec >same machine in a Linux window LTspice4 with wine under Linux: 22 sec > >Machine is a Dell Precision "portable Workstation" 3.5 years old. >"portable" has to be taken with a grain of salt. 240W power supply. > >I have no idea which run was on which CPU. The CPUs all run at pretty >different speed. > >regards, Gerhard > > > >system description: > >gerhard@precision:~$ inxi -CDb >System: Host: precision Kernel: 4.4.0-62-generic x86_64 (64 bit) >Desktop: Cinnamon 2.8.8 > Distro: Linux Mint 17.3 Rosa >Machine: System: Dell product: Precision M6600 v: 01 > Mobo: Dell model: 04YY4M v: A00 Bios: Dell v: A15 date: >09/27/2013 >CPU: Quad core Intel Core i7-2820QM (-HT-MCP-) cache: 8192 KB > clock speeds: max: 3400 MHz 1: 983 MHz 2: 1281 MHz 3: 1301 >MHz 4: 1096 MHz 5: 1564 MHz 6: 1029 MHz > 7: 1119 MHz 8: 868 MHz >Graphics: Card: NVIDIA GF104GLM [Quadro 4000M] > Display Server: X.Org 1.15.1 drivers: nvidia (unloaded: >fbdev,vesa,nouveau) > Resolution: 1920x1080@60.0hz, 2560x1440@60.0hz > GLX Renderer: Quadro 4000M/PCIe/SSE2 GLX Version: 4.5.0 >NVIDIA 367.57 >Network: Card-1: Intel 82579LM Gigabit Network Connection driver: e1000e > Card-2: Intel Centrino Ultimate-N 6300 driver: iwlwifi >Drives: HDD Total Size: 1536.3GB (74.0% used) ID-1: /dev/sda model: >Samsung_SSD_850 size: 1024.2GB > ID-2: /dev/sdb model: SAMSUNG_SSD_830 size: 512.1GB >Info: Processes: 268 Uptime: 13:11 Memory: 2589.1/16003.5MB Client: >Shell (bash) inxi: 2.2.28 > > > >
On my Dell, that sim runs about 10% slower if I plot the waveform during the run. I can imagine that PCs with slow graphics could take a bigger hit. Do VMs add graphics overhead? We once rented a compute farm from Amazon to run a slow sim. It wasn't any faster than our 4-core Dells. -- John Larkin Highland Technology, Inc lunatic fringe electronics