CARV-ICS-FORTH / CARV-ICS-FORTH/FastMap

How to make fastmap support more cpu cores than 32 or 80

Open
#1 4 comments 0 reactions 0 assignees View on GitHub
Dominant language
C
Stars
37
Forks
6
PR merge metrics
No merged PRs in 30d

Description

I tried to run FastMap on a server with 256 cores, and FastMap crashed at `alloc_page_lock`. I read the code and found that FastMap only supports 32 and 80 freelists (or cores) according to `mmap_buffer_hash_table.c` shown below. How to make it variable? I am also confused about setting constants in `shared_defines.h`? Could you show a correct setting with 256 cores? Thank you.

https://github.com/CARV-ICS-FORTH/FastMap/blob/06a2c9387ce6e8c280d7d01fee02b286e6954ef7/driver/mmap_buffer_hash_table.c#L135

https://github.com/CARV-ICS-FORTH/FastMap/blob/06a2c9387ce6e8c280d7d01fee02b286e6954ef7/driver/mmap_buffer_hash_table.c#L280

Contributor guide

No contributing guide indexed for this repository

Research direction

Start by reading the freelist and alloc_page_lock logic at the referenced locations in driver/mmap_buffer_hash_table.c, then inspect the related constants in shared_defines.h. Determine what changes are needed for a 256-core configuration and verify that FastMap no longer crashes with that configuration.

Written by the indexing model from the issue text.

Assessment

Tech stack
c
Domain
operating-systems
Issue type
Feature
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
25/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.