Re: [Gems-users] ruby parameter selection

["soohong p kim" <spkim@xxxxxxxxxx>]

Hi,

Is there anyone who can answer questions below regarding cache latency
parameters for MOESI_CMP_directory (or in general)?
Thanks.

soohong

> L1_RESPONSE_LATENCY - value: 1 - used in MOESI_CMP_directory?
> L2_RESPONSE_LATENCY - value: 6 - used in MOESI_CMP_directory?
> L1_REQUEST_LATENCY - value: 1 - what is the difference between REQUEST and
RESPONSE?
> L2_REQUEST_LATENCY - value: 6 - what is the difference between REQUEST and
RESPONSE?

-----Original Message-----
From: gems-users-bounces@xxxxxxxxxxx [mailto:gems-users-bounces@xxxxxxxxxxx]
On Behalf Of Dan Gibson
Sent: Friday, April 11, 2008 9:32 PM
To: Gems Users
Subject: Re: [Gems-users] ruby parameter selection

Most of the timing variables are protocol-dependent, unfortunately.
Grep through MOESI_CMP_directory to discover which variables it uses, 
and how. I'm no expert on that protocol, so I cannot answer your 
question directly.

Regards,
Dan

Mladen Nikitovic wrote:
> Hi,
>
> I would like to model a pretty simple system with a L1 cache that has an 
> access time of 1 cycle and an L2 access time of 6 cycles + latency of 
> the network.
>
> I have a problem with setting up these parameters in ruby, especially 
> the L1 latency.
>
> There are many parameters that seem related but it seems some are used 
> in some protocols, not all.
>
> I'm using the MOESI_CMP_directory protocol.
>
> I managed to reduce the execution time of the application by changing 
> the ruby_mutliplier from 2 to 1.
>
> The parameters that I'm hesitating about regarding cache latency are the 
> following:
>
> DIRECTORY_CACHE_LATENCY - value: 6 - this latency is used when accessing 
> the L2, right?
> ISSUE_LATENCY - value: 2 - what type of issue is this? where is this 
> issue performed?
>
> CACHE_RESPONSE_LATENCY - value: 12 -  Is this L1 or L2? Is it used in 
> MOESI_CMP_directory protocol?
> L1_RESPONSE_LATENCY - value: 1 - used in MOESI_CMP_directory?
> L2_RESPONSE_LATENCY - value: 6 - used in MOESI_CMP_directory?
>
> RECYCLE_LATENCY - value: 3 - when is recycling performed?
> L2_RECYCLE_LATENCY - value: 5 - when is recycling performed?
>
> L1_REQUEST_LATENCY - value: 1 - what is the difference between REQUEST 
> and RESPONSE?
> L2_REQUEST_LATENCY - value: 6 - what is the difference between REQUEST 
> and RESPONSE?
>
> SEQUENCER_TO_CONTROLLER_LATENCY- value: 4 - should this be 1 or can I 
> put it to 0?
>
> One general question is whether I need to assign 0 to any of these 
> values to achieve my objective.
>
> Hope you have the time to sort out the meaning of these parameters.
>
> Regards,
> Mladen
>
> _______________________________________________
> Gems-users mailing list
> Gems-users@xxxxxxxxxxx
> https://lists.cs.wisc.edu/mailman/listinfo/gems-users
> Use Google to search the GEMS Users mailing list by adding
"site:https://lists.cs.wisc.edu/archive/gems-users/"; to your search.
>
>
>   

-- 
http://www.cs.wisc.edu/~gibson [esc]:wq!

_______________________________________________
Gems-users mailing list
Gems-users@xxxxxxxxxxx
https://lists.cs.wisc.edu/mailman/listinfo/gems-users
Use Google to search the GEMS Users mailing list by adding
"site:https://lists.cs.wisc.edu/archive/gems-users/"; to your search.