(netbsd from csv2(git/hg)) of version control systems. minimum memory

[mocore]

https://mail-index.netbsd.org/tech-repository/2025/01/04/msg000805.html

any one know how comparable git min memory is on Linux ?
( and or ... used any of the git's newer partial / single file/chunk access ??) 

** low-memory issues

> * Performance implications of the desired VCS system, especially
>   for hosts with low or moderate amounts of memory.

hg can operate in about 512 MB of working memory, without the evolve
extension for revising work-in-progress development topics.  (With the
evolve extension, requires about 3 GB.)

XXX TBD: Test whether remotefilelog reduces memory usage.

git can operate in about 512 MB of working memory, with the following
tunables in ~/.gitconfig (with the caveat that they may increase disk
space usage):

[core]
   packedGitWindowSize = 1k
   packedGitLimit = 1k
   deltaBaseCacheLimit = 1k
   compression = 0
   loosecompression = 0
   bigFileThreshold = 1m

[pack]
   window = 1
   depth = 1
   windowMemory = 1k
   deltaCacheSize = 1k
   deltaCacheLimit = 1
   threads = 1
   packSizeLimit = 1m

While this memory usage considerably higher than CVS required, it's
also about the minimum you need anyway to build NetBSD.

>   Whether low performance hosts:
>
>     - will be able to use the new system fully; or

Below around 512 MB, not fully.

>     - will be able to use a degraded mode that will allow at
>       least HEAD and branch checkouts and commits (but perhaps
>       without the ability to create new branches or to merge); or

Systems with 256 MB -- and possibly much less than that -- should be
able to work in Git sparse checkouts of shallow filtered clones.