162586 - make sure cache size is reasonable relative to available resources

Status: RESOLVED WONTFIX

(Core :: Networking: Cache, defect)

Description

[Darin Fisher]

There are no checks on the value of cache size. Cache should reject values
that don't make sense (0-90% of max memory/disc or something?), and the UI 
should assist. Becomes more important in kiosk mode.

Comment 1

[gordon]

Is kiosk mode well defined?  I would think there are many preferences that
shouldn't be settable in kiosk mode, and cache size should be one of them.

Fixing bug 105344 would obviate/satisfy the need for specific memory cache size
checks.  It will probably be fixed soon.

Comment 2

[benc]

What else needs to be done here? One smartness check I'd like to see, not
directly related to size, would be not putting a disk cache into obviously bad
places (like memory mapped disk partitions and/or too small partitions).

Comment 3

[RalfG]

I agree, imagine multiuser settings on a company/school roolout: Where users have a quota of 100 MB, and traffic is cached by some proxy, anyway, there is no sense for a default cache size of 50 MB. My suggestions (alternatives):

(a) Set default cache size down to 8 MB.
(b) Whenever there is a proxy defined, don't cache at all (max.: 4 MB)
(c) Don't cache to non-local home directories (don't know how to check
    for this in general.

Comment 4

[Malbrouck]

I believe company/school sysadmins will tune the cache size when users have a quota defined.

IE is now setting 1GB as default cache size and both Google chrome and Safari don't let the user to set its cache size (in order to use as much disk space needed to do good caching).

Web sites' content has grown over the last years but it seems Firefox is still using 50MB as default disk cache size (since 2004 !). It could be good to have a big cache size even for users having high-speed DSL connections. Today Firefox' default cache size is so small it's not possible to cache a few youtube videos.

So I think a big cache with good indexing of objects in memory, powerful search algorithm to find if the object is in the cache (some btree stuff) and a smart cache object replacement algorithm could be a good performace enhancement for Firefox.

Your thoughts ?