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Setting the Throttling in SIMH? |
vmsfreak01
Member
Posts: 41
Joined: 19.06.08 |
| Posted on June 28 2008 09:26 |
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Hi guys,
What setting should I use for the an emulator (SIMH) to reduce the CPU load cycles as low as possible. I got this from the SIMH manual but what number should I set for each below: Please dont get me wrong, this is not a question on how to use the emulator itself, but what would be the ideal number to set in MIPS, KIPS, or percent of host time should I enter to really really lower the CPU load and temp when running this application on Windows?
In other words, I do not know whats the IDEAL setting for all of these units as below. So I need a number for all these units below in order to reduce the number of CPU load or cycles processed by thei emulator. All I need is a number..Dont worry, I know the commands to enter these,
But...I really want an ideal number to reduce the CPU load for each of these...Thx.
Be advised: I have THROTTLING DISABLED by default
SET THROTTLE xM set execution rate to x mips
SET THROTTLE xK set execution rate to x kips
SET THROTTLE x% limit simulator to x% of host time
Thanks.
Edited by vmsfreak01 on June 28 2008 09:44 |
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RE: Setting the Throttling in SIMH? |
vmsfreak01
Member
Posts: 41
Joined: 19.06.08 |
| Posted on June 28 2008 21:36 |
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Hi,
Thanks.
Now that I have my VAX.INI setup to automatically load the CPU as below. How can I make it automatically SET CPU IDLE=VMS ???
Where and what line should I add this command in my VAX.INI file?
I did a test, and it still showed the CPU at 100 percent...And CPU IDLE was enabled already Is there anyway to I can set the CPU at a lower CPU usage or load? The CPU load spikes only when logging into the VMS DCL command. The only time the CPU load diminishes, is when I halt the VMS and switch into the SIMH command line.
And when I do nothing in the VMS command line, it still spikes to 100 percent...
VAX simulator V3.8-0
sim> set rq0 ra90
sim> att rq0 new_vms.dsk
sim> att rq1 vms.iso
sim> boot cpu
Thx.
Edited by vmsfreak01 on June 28 2008 22:03 |
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RE: Setting the Throttling in SIMH? |
martinv2
Member
Posts: 107
Location: Goslar, Germany
Joined: 02.10.07 |
| Posted on June 29 2008 07:00 |
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Now that I have my VAX.INI setup to automatically load the CPU as below. How can I make it automatically SET CPU IDLE=VMS ???
Where and what line should I add this command in my VAX.INI file?
Add it anywhere you want before the BOOT CPU command.
Is there anyway to I can set the CPU at a lower CPU usage or load?
That's what throttling is for. You already found the right command - SET THROTTLE. No idea, however, what are good values to use. And: the simh_doc.pdf says
Some simulators implement a different form of resource management called idling. Idling suspends simulated execution whenever the program running on the simulator is doing nothing, and runs the simulator at full speed when there is work to do. Throttling and idling are mutually exclusive.
This could mean that throttling doesn't work with the VAX emulator, as it does have the SET IDLE command. Or it merely says that you can't use both.
I'd suggest you pose this question (and other SIMH questions) in a more specialized forum: There's a SIMH mailing list; for details see http://simh.trailing-edge.com/help.html
The CPU load spikes only when logging into the VMS DCL command. The only time the CPU load diminishes, is when I halt the VMS and switch into the SIMH command line.
And when I do nothing in the VMS command line, it still spikes to 100 percent...
That's funny. Granted that the simulator takes all of the CPU if I let it do some work (like during startup, or when I tell it to go through all of the directories on disk), but when it waits at the DCL prompt, it only uses 2 to 15% CPU on my WinXP laptop.
cu,
Martin
http://de.openvms.org/martinv/ |
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| Author |
RE: Setting the Throttling in SIMH? |
vmsfreak01
Member
Posts: 41
Joined: 19.06.08 |
| Posted on June 29 2008 07:18 |
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Hi,
On my laptop, the CPU usage now is around 4 to 10 percent...
But it does spike on my desktop PC...
Well, anyway, if too paranoid about this, I just will not use it on the PC...Simple as that.
Wait a second!!!!!!!!! I just checked my CD that I had burned SIMH on WITH the VAX.INI file...and guess what...Its alread added on their...But..I cannot recall if I really did added or not..Strange...
LOAD -r KA655x.BIN
LOAD -n NVRAM.BIN
SET RQ0 RA90
ATTACH RQ0 new_vms.dsk
SET RQ1 RRD40
ATTACH RQ1 vms.iso
SET CPU IDLE=VMS
BOOT CPU
Thanks for your support as always.
Edited by vmsfreak01 on June 29 2008 07:24 |
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| Author |
RE: Setting the Throttling in SIMH? |
vmsfreak01
Member
Posts: 41
Joined: 19.06.08 |
| Posted on June 29 2008 08:50 |
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Hi,
You know what....Thats my same exact guess was that the emulator runs less CPU usage for DUO-Core processors....As my PC is still running on an Pentium-4...
You may hit the nail on that one... |
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RE: Setting the Throttling in SIMH? |
vmsfreak01
Member
Posts: 41
Joined: 19.06.08 |
| Posted on June 29 2008 09:30 |
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Ok, I did another test on my PC, and the CPU is now around 4 to 10%
CPU Temp is 52 C.
So, the IDLE setting to ENABLED really works!!!!!
So the only time it really spikes, is VMS boot-up...then when it waits after logging in..then all seems to be down around 5 %. to 0 %
Edited by vmsfreak01 on June 29 2008 09:46 |
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| Author |
RE: Setting the Throttling in SIMH? |
vmsfreak01
Member
Posts: 41
Joined: 19.06.08 |
| Posted on July 01 2008 19:30 |
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Hi,
Well, it still spikes up to 100 percent..
How come sometimes its does not and and mostly it does?
Is my vax.ini file correct in regards to the set cpu idle command?
LOAD -r KA655x.BIN
LOAD -n NVRAM.BIN
SET RQ0 RA90
ATTACH RQ0 new_vms.dsk
SET RQ1 RRD40
ATTACH RQ1 vms.iso
SET CPU IDLE=VMS
BOOT CPU
Hi,
Just a thought here to add:
In the VAX.INI file, can I add the SET THROTTLE along with the SET CPU IDLE to ensure that it is set to THROTTLING WHEN THE emulator is booted?
If, yes, then would it be added under or above the SET CPU IDLE command?
Edited by vmsfreak01 on July 01 2008 23:24 |
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RE: Setting the Throttling in SIMH? |
martinv2
Member
Posts: 107
Location: Goslar, Germany
Joined: 02.10.07 |
| Posted on July 02 2008 00:45 |
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Just a thought here to add:
In the VAX.INI file, can I add the SET THROTTLE along with the SET CPU IDLE to ensure that it is set to THROTTLING WHEN THE emulator is booted?
If, yes, then would it be added under or above the SET CPU IDLE command?
Scroll up from this message to my message of June 29 2008 08:00. There you'll find the answer to your question.
http://de.openvms.org/martinv/
Edited by martinv2 on July 02 2008 00:45 |
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| Author |
RE: Setting the Throttling in SIMH? |
vmsfreak01
Member
Posts: 41
Joined: 19.06.08 |
| Posted on July 02 2008 01:03 |
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Add it anywhere you want before the BOOT CPU command.
Now I understand this part.
But, if I add the command SET THROTTLE to the VAX.INI file, along with the SET IDLE CPU command, will this actually reduce the CPU load even further?
Also,
Does the emulator have to wait for a specific time in order to set the CPU in to idle?
Thanks.
Edited by vmsfreak01 on July 02 2008 01:06 |
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| Author |
RE: Setting the Throttling in SIMH? |
martinv2
Member
Posts: 107
Location: Goslar, Germany
Joined: 02.10.07 |
| Posted on July 02 2008 01:51 |
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Add it anywhere you want before the BOOT CPU command.
Now I understand this part.
But, if I add the command SET THROTTLE to the VAX.INI file, along with the SET IDLE CPU command, will this actually reduce the CPU load even further?
<sigh>
That wan't the text I had in mind. It was:
This could mean that throttling doesn't work with the VAX emulator, as it does have the SET IDLE command. Or it merely says that you can't use both.
together with the manual citation above it.
Does the emulator have to wait for a specific time in order to set the CPU in to idle?
As I've understood it, it looks for some tight CPU loops that might indicate an idling CPU.
But these are discussions for the SIMH mailing list (again: see above), as they don't have to do anything with VAXen or VMS.
http://de.openvms.org/martinv/ |
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