Easter sermon: Of kernels and slocate [was: Slocate hates me (was:Prelink hates me)]

[Fred New]

On April 11, 2004, at 00:52, Bryan O'Sullivan wrote:
> 
> On Sat, 2004-04-10 at 13:03, Simon Perreault wrote:
> > Ok, I found out what the problem was. The culprit is not prelink. It
is 
> > slocate.
<snip>
> Tools like "slocate" are pathological in their behaviour for caches. 
> The cache is meant to help when you need to access the same data again
> and again, which is very common.  However, slocate reads every single
> file in a filesystem once, so the caches balloon up in size with data
> that they don't need to contain.
<snip again>

We have a similar problem with databases: reports that need to scan an
entire database fill the database cache with unnecessary data, while
only a fraction of the database is usually active.  In the database
package I am familiar with, you can set a parameter that limits how much
database cache the reports are allowed to use.  It seems like a similar
parameter for file system cache could be created for programs like
slocate.

Fred