[systemd-devel] Slow startup of systemd-journal on BTRFS

[Tollef Fog Heen]

]] Lennart Poettering 

(trimming Ccs)

> I am invoking fallocate() in advance, because we write those files with
> mmap() and that of course would normally triggered SIGBUS already on the
> most boring of reasons, such as disk full/quota full or so. Hence,
> before we do anything like that, we invoke fallocate() to ensure that
> the space is actually available... As far as I can see, that pretty much
> in line with what fallocate() is supposed to be useful for, the man page
> says this explicitly:

OOI, why not use write + read-only mmap for reading?  In testing
performance for another project, that's significantly faster than rw
mmap.

-- 
Tollef Fog Heen
UNIX is user friendly, it's just picky about who its friends are