[
https://issues.apache.org/jira/browse/HBASE-4752?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13146769#comment-13146769
]
Ted Yu commented on HBASE-4752:
-------------------------------
Here are some statistics about how widely HBase codebase uses class(es) from
Guava:
{code}
zhihyu$ find src/main -name '*.java' -exec grep Precondition {} \; -print | head
import com.google.common.base.Preconditions;
Preconditions.checkArgument(n >= 0, "limit be positive %s", n);
Preconditions.checkArgument(filterArguments.size() == 1,
src/main/java/org/apache/hadoop/hbase/filter/ColumnCountGetFilter.java
import com.google.common.base.Preconditions;
Preconditions.checkArgument(limit >= 0, "limit must be positive %s", limit);
Preconditions.checkArgument(offset >= 0, "offset must be positive %s",
offset);
Preconditions.checkArgument(filterArguments.size() == 2,
src/main/java/org/apache/hadoop/hbase/filter/ColumnPaginationFilter.java
import com.google.common.base.Preconditions;
zhihyu$ find src/main -name '*.java' -exec grep Precondition {} \; | wc
96 270 5149
{code}
If usage of Preconditions is recommended, we shouldn't worry about using
MinMaxPriorityQueue which already appears in our codebase.
I am also open to finding other implementations for double-ended queue.
> Don't create an unnecessary LinkedList when evicting from the BlockCache
> ------------------------------------------------------------------------
>
> Key: HBASE-4752
> URL: https://issues.apache.org/jira/browse/HBASE-4752
> Project: HBase
> Issue Type: Improvement
> Components: performance, regionserver
> Affects Versions: 0.90.4
> Reporter: Benoit Sigoure
> Assignee: Ted Yu
> Priority: Minor
> Fix For: 0.94.0
>
> Attachments:
> 0001-HBASE-4752-Don-t-create-an-unnecessary-LinkedList-wh.patch,
> 4752-trunk-v2.txt, 4752-trunk.txt
>
>
> When evicting from the BlockCache, the code creates a LinkedList containing
> every single block sorted by access time. This list is created from a
> PriorityQueue. I don't believe it is necessary, as the PriorityQueue can be
> used directly.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:
https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
