Hi Shawn
No affense to your work,I am still confusing about the cache warm
processing about your explanation.So I check the warm method of
FastLRUCache as [1].
As far as I see,there is no values refresh during the the warm
processing. the *regenerator.regenerateItem* just put the old value to the
new cache.
Did I miss anything?
[1]------------------------------------------------------------------------------
public void warm(SolrIndexSearcher searcher, SolrCache old) {
if (regenerator == null) return;
long warmingStartTime = System.nanoTime();
FastLRUCache other = (FastLRUCache) old;
// warm entries
if (isAutowarmingOn()) {
int sz = autowarm.getWarmCount(other.size());
Map items = other.cache.getLatestAccessedItems(sz);
Map.Entry[] itemsArr = new Map.Entry[items.size()];
int counter = 0;
for (Object mapEntry : items.entrySet()) {
itemsArr[counter++] = (Map.Entry) mapEntry;
}
for (int i = itemsArr.length - 1; i >= 0; i--) {
try {
boolean continueRegen = regenerator.regenerateItem(searcher,
this, old, itemsArr[i].getKey(), itemsArr[i].getValue());
if (!continueRegen) break;
}
catch (Exception e) {
SolrException.log(log, "Error during auto-warming of key:" +
itemsArr[i].getKey(), e);
}
}
}
warmupTime = TimeUnit.MILLISECONDS.convert(System.nanoTime() -
warmingStartTime, TimeUnit.NANOSECONDS);
}
2014-07-25 21:45 GMT+08:00 Shawn Heisey <s...@elyograg.org>:
> On 7/24/2014 8:45 PM, YouPeng Yang wrote:
> > To Matt
> >
> > Thank you,your opinion is very valuable ,So I have checked the source
> > codes about how the cache warming up. It seems to just put items of the
> > old caches into the new caches.
> > I will pull Mark Miller into this discussion.He is the one of the
> > developer of the Solr whom I had contacted with.
> >
> > To Mark Miller
> >
> > Would you please check out what we are discussing in the last two
> > posts.I need your help.
>
> Matt is completely right. Any commit can drastically change the Lucene
> document id numbers. It would be too expensive to determine which
> numbers haven't changed. That means Solr must throw away all cache
> information on commit.
>
> Two of Solr's caches support autowarming. Those caches use queries as
> keys and results as values. Autowarming works by re-executing the top N
> queries (keys) in the old cache to obtain fresh Lucene document id
> numbers (values). The cache code does take *keys* from the old cache
> for the new cache, but not *values*. I'm very sure about this, as I
> wrote the current (and not terribly good) LFUCache.
>
> Thanks,
> Shawn
>
>
