Re: [PATCH prototype] [0/8] Predictive bitmaps for ELF executables

Ulrich Drepper
2008-03-24T19:42:35Z

On Sun, Mar 23, 2008 at 10:16 PM, Nicholas Miell <nmiell@comcast.net> wrote:
> The limit is filesystem dependent -- I think ext2/3s is something like
> 4k total for attribute names and values per inode.
>
> That's more than enough space for the largest executable on my system
> (emacs at 36788160 bytes) which would have a 1123 byte predictive bitmap
> (plus space for the name e.g. "system.predictive_bitmap"). The bitmap
> also could be compressed.

4k attribute means support for about 32768 pages. That's a total of
134MB. I think this qualifies as sufficient. Also, I assume the
attribute limit is just a "because nobody needed more so far" limit
and could in theory be extended.