Thanks, Andreas. This makes sense.

On Wed, Apr 15, 2015 at 5:26 PM, Andreas Hansson <[email protected]>
wrote:

>  Hi Patrick,
>
>  When it comes to the stores you are looking at a rather small number of
> operations, and my guess is that they are still in the DRAM write queues.
> These queues are not drained at the moment once the writes fall below the
> “low water mark”.
>
>  Andreas
>
>   From: Patrick <[email protected]>
> Reply-To: gem5 users mailing list <[email protected]>
> Date: Wednesday, 15 April 2015 19:13
> To: gem5 users mailing list <[email protected]>
> Subject: [gem5-users] bytesWritten < (8 * number of 64-bit stores to
> unique addresses)
>
>  I am looking at stats.txt for the amount of data written to the DRAM
> during the execution of a process in full system mode. I looked at the
> execution trace, and there are at least 512 64-bit stores to unique
> addresses. However, stats.txt reports only 2,304 "bytesWritten" to the
> memory. It is a 4-channel memory configuration. "stats.txt" reports 1,152
> "bytesWritten" on channel 0, 0 "bytesWritten" to channel 1, 0
> "bytesWritten" to channel 2, and 1,152 "bytesWritten" to channel 3.
>
>  Does anyone know what would cause this? I thought maybe the data might
> be getting left in the caches, but I am waiting until the process exits
> before calling m5 resetstats. The "bytesReadDRAM" is less than expected,
> also, based on the number of loads in the instruction trace. I thought
> perhaps this was because no-write allocate was being used, but the
> discussion linked below suggests that default is to use write-allocate. I
> can't find where this is configured in gem5, so I'm not able to check this
> at the moment.
>
>  http://comments.gmane.org/gmane.comp.emulators.m5.users/12597
>
>  Any help is appreciated.
>
>   ​-​
> Patrick
>
> -- IMPORTANT NOTICE: The contents of this email and any attachments are
> confidential and may also be privileged. If you are not the intended
> recipient, please notify the sender immediately and do not disclose the
> contents to any other person, use it for any purpose, or store or copy the
> information in any medium. Thank you.
>
> ARM Limited, Registered office 110 Fulbourn Road, Cambridge CB1 9NJ,
> Registered in England & Wales, Company No: 2557590
> ARM Holdings plc, Registered office 110 Fulbourn Road, Cambridge CB1 9NJ,
> Registered in England & Wales, Company No: 2548782
>
> _______________________________________________
> gem5-users mailing list
> [email protected]
> http://m5sim.org/cgi-bin/mailman/listinfo/gem5-users
>
_______________________________________________
gem5-users mailing list
[email protected]
http://m5sim.org/cgi-bin/mailman/listinfo/gem5-users

Reply via email to