lucene-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Michael McCandless (JIRA)" <j...@apache.org>
Subject [jira] Commented: (LUCENE-1313) Realtime Search
Date Wed, 06 May 2009 21:53:30 GMT

    [ https://issues.apache.org/jira/browse/LUCENE-1313?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12706611#action_12706611
] 

Michael McCandless commented on LUCENE-1313:
--------------------------------------------

{quote}
> I don't think that's needed. I think whenever IW makes a
> change to the RAMDir, which is easily tracked, it pushes to DW
> the new RAMDir size.

Because we know the IW.ramdir is a RAMDirectory implementation,
we can use sizeInBytes? It's synchronized, maybe we want a
different method that's not? It seems like keeping track of all
files writes outside ramdir is going to be difficult? For
example when we do deletes via SegmentReader how would we keep
track of that?
{quote}

We should definitely just use the sizeInBytes() method.

I'm saying that IW knows when it writes new files to the RAMDir
(flushing deletes, flushing new segment) and it's only at those times
that it should call sizeInBytes() and push that value down to DW.

{quote}
> That, and because it's only used to determine CFS or not,
> which we've turned off for RAMDir.

So we let the user set the RAMMergePolicy but not get it?
{quote}

Oh, we should add a getter (getRAMMergePolicy, not getLogMergePolicy)
for it, but it should return MergePolicy not LogMergePolicy.

{quote}
> The thread is simply launched w/o checking
> maxThreadCount, if the merge is in RAM.

Hmm... We can't just create threads and let them be garbage
collected as JVMs tend to throw OOMs with this. If we go down
this route of a single CMS, maybe we can borrow some code from
an Apache project that's implemented a threadpool.
{quote}

This is how CMS has always been.  It launches threads relatively
rarely -- this shouldn't lead to OOMs.  One can always subclass CMS if
this is somehow a problem.  Or we could modify CMS to pool its threads
(as a new issue)?


> Realtime Search
> ---------------
>
>                 Key: LUCENE-1313
>                 URL: https://issues.apache.org/jira/browse/LUCENE-1313
>             Project: Lucene - Java
>          Issue Type: New Feature
>          Components: Index
>    Affects Versions: 2.4.1
>            Reporter: Jason Rutherglen
>            Priority: Minor
>             Fix For: 2.9
>
>         Attachments: LUCENE-1313.jar, LUCENE-1313.patch, LUCENE-1313.patch, LUCENE-1313.patch,
LUCENE-1313.patch, LUCENE-1313.patch, LUCENE-1313.patch, LUCENE-1313.patch, LUCENE-1313.patch,
LUCENE-1313.patch, lucene-1313.patch, lucene-1313.patch, lucene-1313.patch, lucene-1313.patch
>
>
> Realtime search with transactional semantics.  
> Possible future directions:
>   * Optimistic concurrency
>   * Replication
> Encoding each transaction into a set of bytes by writing to a RAMDirectory enables replication.
 It is difficult to replicate using other methods because while the document may easily be
serialized, the analyzer cannot.
> I think this issue can hold realtime benchmarks which include indexing and searching
concurrently.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


---------------------------------------------------------------------
To unsubscribe, e-mail: java-dev-unsubscribe@lucene.apache.org
For additional commands, e-mail: java-dev-help@lucene.apache.org


Mime
View raw message