On 2006-11-14 at 13:18 +0100, Marten Lehmann wrote:
> 2. Why aren't flags stored in the file name, too? I used to see that
> with Maildirs and it is very clever: Flags are permanent and aren't lost
> if the index is broken. Anyway, the index speeds up access to the flags
> and the index can be rebuild from the flags in the filename. The
> flag-structure might be adopted from the Maildir-specification.
(1) That doesn't allow for per-user flags, only global flags. Shared
folders.
(2) With large-scale servers, this means that every flag-based action
involves a rename, which means file-system internal locks on the
directory. This doesn't scale at the high end, but isn't a problem
for small to mid-size installations. File renames are not free and
they push the atomicity where you really don't want to be pushing it
for scalability, although it can be simple.
-Phil, not running high-end Cyrus, but has run a largish mail-system in
previous employment.
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