Commit Graph

3 Commits

Author SHA1 Message Date
Nicolas Lacasse 9db7cfad93 Add a new cache policy FSCACHE_WRITETHROUGH.
The new policy is identical to FSCACHE (which caches everything in memory), but
it also flushes writes to the backing fs agent immediately.

All gofer cache policy decisions have been moved into the cachePolicy type.
Previously they were sprinkled around the codebase.

There are many different things that we cache (page cache, negative dirents,
dirent LRU, unstable attrs, readdir results....), and I don't think we should
have individual flags to control each of these.  Instead, we should have a few
high-level cache policies that are consistent and useful to users.  This
refactoring makes it easy to add more such policies.

PiperOrigin-RevId: 201206937
Change-Id: I6e225c382b2e5e1b0ad4ccf8ca229873f4cd389d
2018-06-19 11:10:11 -07:00
Fabricio Voznika ac01f245ff Skip atime and mtime update when file is backed by host FD
When file is backed by host FD, atime and mtime for the host file and the
cached attributes in the Sentry must be close together. In this case,
the call to update atime and mtime can be skipped. This is important when
host filesystem is using overlay because updating atime and mtime explicitly
forces a copy up for every file that is touched.

PiperOrigin-RevId: 196176413
Change-Id: I3933ea91637a071ba2ea9db9d8ac7cdba5dc0482
2018-05-10 14:59:40 -07:00
Googler d02b74a5dc Check in gVisor.
PiperOrigin-RevId: 194583126
Change-Id: Ica1d8821a90f74e7e745962d71801c598c652463
2018-04-28 01:44:26 -04:00