Author: kturner
Date: Tue Apr 17 17:26:36 2012
New Revision: 1327191
URL: http://svn.apache.org/viewvc?rev=1327191&view=rev
Log:
ACCUMULO-494 documented how walog settings could limit tserver memory usage.
Modified:
accumulo/branches/1.4/docs/config.html
accumulo/branches/1.4/src/core/src/main/java/org/apache/accumulo/core/conf/Property.java
Modified: accumulo/branches/1.4/docs/config.html
URL:
http://svn.apache.org/viewvc/accumulo/branches/1.4/docs/config.html?rev=1327191&r1=1327190&r2=1327191&view=diff
==============================================================================
--- accumulo/branches/1.4/docs/config.html (original)
+++ accumulo/branches/1.4/docs/config.html Tue Apr 17 17:26:36 2012
@@ -403,7 +403,7 @@ $HADOOP_HOME/lib/[^.].*.jar,
<td><b><a href='#MEMORY'>memory</a></b></td>
<td>yes</td>
<td><pre>1G</pre></td>
- <td>Maximum amount of memory all tablets in memory maps can use.</td>
+ <td>Maximum amount of memory that can be used to buffer data written to a
tablet server. There are two other properties that can effectively limit
memory usage table.compaction.minor.logs.threshold and tserver.walog.max.size.
Ensure that table.compaction.minor.logs.threshold * tserver.walog.max.size >=
this property.</td>
</tr>
<tr >
<td>tserver.memory.maps.native.enabled</td>
@@ -501,7 +501,7 @@ $HADOOP_HOME/lib/[^.].*.jar,
<td><b><a href='#MEMORY'>memory</a></b></td>
<td>yes</td>
<td><pre>1G</pre></td>
- <td>The maximum size for each write-ahead log</td>
+ <td>The maximum size for each write-ahead log. See comment for property
tserver.memory.maps.max</td>
</tr>
<tr><td colspan='5'><a name='LOGGER_PREFIX'
class='large'>logger.*</a></td></tr>
<tr><td colspan='5'><i>Properties in this category affect the behavior of
the write-ahead logger servers</i></td></tr>
@@ -775,7 +775,7 @@ $HADOOP_HOME/lib/[^.].*.jar,
<td><b><a href='#COUNT'>count</a></b></td>
<td>yes</td>
<td><pre>3</pre></td>
- <td>When there are more than this many write-ahead logs against a tablet,
it will be minor compacted.</td>
+ <td>When there are more than this many write-ahead logs against a tablet,
it will be minor compacted. See comment for property
tserver.memory.maps.max</td>
</tr>
<tr >
<td>table.failures.ignore</td>
Modified:
accumulo/branches/1.4/src/core/src/main/java/org/apache/accumulo/core/conf/Property.java
URL:
http://svn.apache.org/viewvc/accumulo/branches/1.4/src/core/src/main/java/org/apache/accumulo/core/conf/Property.java?rev=1327191&r1=1327190&r2=1327191&view=diff
==============================================================================
---
accumulo/branches/1.4/src/core/src/main/java/org/apache/accumulo/core/conf/Property.java
(original)
+++
accumulo/branches/1.4/src/core/src/main/java/org/apache/accumulo/core/conf/Property.java
Tue Apr 17 17:26:36 2012
@@ -84,7 +84,8 @@ public enum Property {
"To find a tablets split points, all index files are opened. This
setting determines how many index "
+ "files can be opened at once. When there are more index files than
this setting multiple passes "
+ "must be made, which is slower. However opening too many files at
once can cause problems."),
- TSERV_WALOG_MAX_SIZE("tserver.walog.max.size", "1G", PropertyType.MEMORY,
"The maximum size for each write-ahead log"),
+ TSERV_WALOG_MAX_SIZE("tserver.walog.max.size", "1G", PropertyType.MEMORY,
+ "The maximum size for each write-ahead log. See comment for property
tserver.memory.maps.max"),
TSERV_MAJC_DELAY("tserver.compaction.major.delay", "30s",
PropertyType.TIMEDURATION,
"Time a tablet server will sleep between checking which tablets need
compaction."),
TSERV_MAJC_THREAD_MAXOPEN("tserver.compaction.major.thread.files.open.max",
"10", PropertyType.COUNT,
@@ -95,7 +96,11 @@ public enum Property {
+ "This setting determines how much time an unused map file should be
kept open until it is closed."),
TSERV_NATIVEMAP_ENABLED("tserver.memory.maps.native.enabled", "true",
PropertyType.BOOLEAN,
"An in-memory data store for accumulo implemented in c++ that increases
the amount of data " + "accumulo can hold in memory and avoids Java GC
pauses."),
- TSERV_MAXMEM("tserver.memory.maps.max", "1G", PropertyType.MEMORY, "Maximum
amount of memory all tablets in memory maps can use."),
+ TSERV_MAXMEM(
+ "tserver.memory.maps.max",
+ "1G",
+ PropertyType.MEMORY,
+ "Maximum amount of memory that can be used to buffer data written to a
tablet server. There are two other properties that can effectively limit
memory usage table.compaction.minor.logs.threshold and tserver.walog.max.size.
Ensure that table.compaction.minor.logs.threshold * tserver.walog.max.size >=
this property."),
TSERV_MEM_MGMT("tserver.memory.manager",
"org.apache.accumulo.server.tabletserver.LargestFirstMemoryManager",
PropertyType.CLASSNAME,
"An implementation of MemoryManger that accumulo will use."),
TSERV_SESSION_MAXIDLE("tserver.session.idle.max", "1m",
PropertyType.TIMEDURATION, "maximum idle time for a session"),
@@ -213,7 +218,7 @@ public enum Property {
+ "compactions only take place for tablets that have one or more map
files."),
TABLE_SPLIT_THRESHOLD("table.split.threshold", "1G", PropertyType.MEMORY,
"When combined size of files exceeds this amount a tablet is split."),
TABLE_MINC_LOGS_MAX("table.compaction.minor.logs.threshold", "3",
PropertyType.COUNT,
- "When there are more than this many write-ahead logs against a tablet,
it will be minor compacted."),
+ "When there are more than this many write-ahead logs against a tablet,
it will be minor compacted. See comment for property tserver.memory.maps.max"),
TABLE_MINC_COMPACT_IDLETIME("table.compaction.minor.idle", "5m",
PropertyType.TIMEDURATION,
"After a tablet has been idle (no mutations) for this time period it may
have its "
+ "in-memory map flushed to disk in a minor compaction. There is no
guarantee an idle " + "tablet will be compacted."),
