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https://issues.apache.org/jira/browse/PHOENIX-2417?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15096763#comment-15096763
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James Taylor commented on PHOENIX-2417:
---------------------------------------
Thanks for the update. I noticed one issue that may be causing the failures. In
BaseResultIterators.incrementGuidePostStreamToCurrentKey you need to use the
Bytes.compareTo() that takes an offset and length as the underlying
ImmutableBytesWritable may have a length set that's less than byte[].length.
{code}
+ private int incrementGuidePostStreamToCurrentKey(PrefixByteDecoder
decoder, DataInput input, byte[] currentKey) {
+ int count = 0;
+ try {
+ while (Bytes.compareTo(currentKey, CodecUtils.decode(decoder,
input).get()) <= 0) {
+ count++;
+ }
+ } catch (EOFException e) {}
+ return count;
+ }
+
{code}
> Compress memory used by row key byte[] of guideposts
> ----------------------------------------------------
>
> Key: PHOENIX-2417
> URL: https://issues.apache.org/jira/browse/PHOENIX-2417
> Project: Phoenix
> Issue Type: Sub-task
> Reporter: James Taylor
> Assignee: Ankit Singhal
> Fix For: 4.7.0
>
> Attachments: PHOENIX-2417.patch, PHOENIX-2417_encoder.diff,
> PHOENIX-2417_v2_wip.patch
>
>
> We've found that smaller guideposts are better in terms of minimizing any
> increase in latency for point scans. However, this increases the amount of
> memory significantly when caching the guideposts on the client. Guidepost are
> equidistant row keys in the form of raw byte[] which are likely to have a
> large percentage of their leading bytes in common (as they're stored in
> sorted order. We should use a simple compression technique to mitigate this.
> I noticed that Apache Parquet has a run length encoding - perhaps we can use
> that.
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