Hi, Alan,
If database cache is changed locally, we don’t want to bring remote copy to
overwrite it as the remote copy doesn’t carry local changes (ideally, we shall
also apply local changes to the remote copy images we bring in from db, but we
are not there yet). That’s why we skip the update if there’s local changes, and
wait for the next iteration to sync with remote. isDatabaseCacheDirty is
initially set to false unless there’s local update, and will be reset during
cache swap, thus give a chance for the next iteration to update the cache if
there’s no local changes.
Thanks,
Daniel
On 2/6/18, 11:57 AM, "Alan Gates" <alanfga...@gmail.com> wrote:
I’m confused by the following code in the CachedStore. This in in the
CacheUpdateMasterWork thread, in the updateDatabases method (which is
called by update()):
*// Skip background updates if we detect change*
*if *(*isDatabaseCacheDirty*.compareAndSet(*true*, *false*)) {
*LOG*.debug(*"Skipping database cache update; the database list we have
is dirty."*);
*return*;
}
Why are we not updating the cache if we’ve dirtied it? Also, AFAICT no one
ever sets isDatabaseCacheDirty to false, meaning once one database is
created the cache will never be updated. Am I missing something?
Alan.
