Question about using SRRIP replacement policy

[Myeongjae Jang]

Hello, SniperSim directors.

I'm Myeongjae Jang, a Ph.D. course student in KAIST, South Korea.

 

I'm using SniperSim for my research and there are some problems using SniperSim.

 

I want to compare performance between using LRU and SRRIP replacement policies.

When I tried to use SRRIP, SniperSim said that SRRIP needs 'bits' configuration.

It seems for selecting how many bits are needed for each cache block.

And with Google search, I found that 'bits' configuration should be integer array and the length of array should be same with the number of cache blocks.

 

In this point I have a question.

In my configuration, L1D cache is 32KB size, 8-way, and its cache block size is 64bytes (Same with nehalem.cfg).

Then, 1 set has 4KB (32KB / 8 = 4K) size and there are 64 cache blocks in 1 set (4096 / 64 = 64).

According to my Googling results, it seems that I have to write 64-length array for 'bits' configuration.

Does it mean that I have to type the same number 64 times for 'bits' configuration?

Moreover, if I want to use SRRIP with L3 cache (2M size, 16 way, 64-byte cache block), it will be 256-length array. If I enlarge the cache size, this 'bits' configuration array will also be increased.

 

What I understand is right for using SRRIP?

Are there any possible solutions to use 'bits' configuration easily without typing same integer as several times? Even more than 100 times?

I tried to find some information or manuals about using SRRIP in SniperSim main page, but there were not any thing for it.

 

Please answer about my question.

I'm glad to use SniperSim for my research and I hope this simulator keeps going better and better.

Thank you for reading and answering to my question.

Sincerely,

PS. Sending an e-mail to snip...@googlegroups.com fails. So, I make a message on Google groups with the same content.

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한국과학기술원 KAIST

전산학부 School of Computing

Embedded Computing Laboratory

박사과정 장명재 Ph.D. student Myeongjae Jang

[Aaron Epstein]

The bits for SRRIP are the number of bits needed for holding the re-reference prediction value for each cache block. This should be set in the configuration file.

This is an example config file for configuring the L2 to use SRRIP with 2 bits. This only needs to be done once for each cache level.

[perf_model/l2_cache]

replacement_policy = srrip

[perf_model/l2_cache/srrip]

bits=2  # For 2 bit RRPV

[Myeongjae Jang]

Thank you for reply, Aaron!

I was very worried about making meaningless array for bits configuration.

It will be very helpful for my research.

Thank you again.

2019년 6월 16일 일요일 오전 12시 2분 36초 UTC+9, Aaron 님의 말: