Re: [PATCH] shmem: add shmem_size option, set filesystem size

[Qian Cai <cai@lca.pw>]

> On Oct 7, 2019, at 9:15 PM, -Gary- <me@garybgenett.net> wrote:
> 
> The use case here is a live distribution, where the initramfs is a standard filesystem.  It is common for these types of distributions to unpack root into memory.  Most of them use SquashFS, and resize shmem using a smaller initramfs first.
> 
> https://grml.org
> 
> In my case, I am unpacking straight from the initramfs to alleviate the need for a separate file and packaging everything in an ISO.  It very well could be that I am the only person who has ever needed this, but it has been a requirement for my distribution.
> 
> https://sourceforge.net/projects/gary-os
> https://github.com/garybgenett/gary-os
> 
> It is also possible that other live distributions are taking the approach they are because of the current inability to load an initrd/initramfs directly into memory without manually resizing the shmem filesystem first.
> 
> Since I was in there hacking the feature, anyway, I thought it would be worth submitting.
> 
> At the least, it should be a "#define", or something.  Right now it is a hard-coded magic token.

I am not sure if it worth the complication. Right now, you have the choice of resizing shmem like every body else or increasing your system memory a bit.

If there are more compiling reasons to bump the limit, it is probably more appropriate to make it the default to use something like 75% memory if there isn’t much side-effect.