[MediaWiki-commits] [Gerrit] search/extra[master]: Add new Load Shedding Router
jenkins-bot has submitted this change and it was merged. (
https://gerrit.wikimedia.org/r/370778 )
Change subject: Add new Load Shedding Router
..
Add new Load Shedding Router
Add a new load shedding router than can decide on a query
to run based on load information about the local node. This
should help to ride out problems with less user visible
effect.
TODO (maybe later):
* Custom stats output about how many times it was triggered.
Unfortunately I havn't found any good way to hook into elasticsearch's
stats collection yet.
* Use the size of some thread pool queue as a trigger condition. Have
not investigated how viable this is.
* Use latency percentiles (p95, etc) as a trigger condition
Change-Id: I0abe91ccf2f628b03621a7f7f0fe634c52c039af
---
A docs/degraded_router.md
M src/main/java/org/wikimedia/search/extra/ExtraPlugin.java
A
src/main/java/org/wikimedia/search/extra/router/DegradedRouterQueryBuilder.java
M src/test/java/org/wikimedia/search/extra/QueryBuilderTestUtils.java
A
src/test/java/org/wikimedia/search/extra/router/DegradedRouterBuilderESTest.java
A
src/test/java/org/wikimedia/search/extra/router/DegradedRouterQueryBuilderParserTest.java
M
src/test/java/org/wikimedia/search/extra/router/TokenCountRouterBuilderESTest.java
7 files changed, 445 insertions(+), 3 deletions(-)
Approvals:
jenkins-bot: Verified
DCausse: Looks good to me, approved
diff --git a/docs/degraded_router.md b/docs/degraded_router.md
new file mode 100644
index 000..c727c2f
--- /dev/null
+++ b/docs/degraded_router.md
@@ -0,0 +1,48 @@
+degraded_router
+===
+
+The ```degraded_router``` is a simple query wrapper that allows
+routing queries based on the load of individual node. It's useful
+to prevent overloaded servers from having an outside effect on end
+user latency by running a cheaper query when the server is loaded.
+
+Example
+---
+
+GET /_search
+{
+"degraded_router": {
+"fallback": {
+"phrase_match": {
+"content": "what should we do today?",
+}
+}
+"conditions": [
+{
+"gte": 70,
+"type": "cpu",
+"query": {
+"match": {
+"content": "what should we do today?"
+}
+}
+}
+]
+}
+}
+
+A match query will be issued if system cpu usage is above 70%. Otherwise
+a phrase match query will be issued.
+
+Options
+---
+
+* `fallback` The query to apply if none of the conditions applies.
+* `conditions` Array of conditions (the first that matches wins):
+* `type`: The type of metric to compare against. Can be `cpu` for cpu%, or
+ `load`for 1 minute load average.
+* `predicate` : can be `eq`, `gt`, `gte`, `lt`, or `lte`, the value is the
number
+to compare against the value reported by `type`
+* `query` The query to apply if the condition is met.
+
+Note that the query parser does not check the conditions coherence
diff --git a/src/main/java/org/wikimedia/search/extra/ExtraPlugin.java
b/src/main/java/org/wikimedia/search/extra/ExtraPlugin.java
index 8b69695..229ccaa 100644
--- a/src/main/java/org/wikimedia/search/extra/ExtraPlugin.java
+++ b/src/main/java/org/wikimedia/search/extra/ExtraPlugin.java
@@ -1,7 +1,9 @@
package org.wikimedia.search.extra;
+import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.index.analysis.TokenFilterFactory;
import org.elasticsearch.indices.analysis.AnalysisModule.AnalysisProvider;
+import org.elasticsearch.monitor.os.OsService;
import org.elasticsearch.plugins.AnalysisPlugin;
import org.elasticsearch.plugins.Plugin;
import org.elasticsearch.plugins.ScriptPlugin;
@@ -11,6 +13,7 @@
import org.wikimedia.search.extra.fuzzylike.FuzzyLikeThisQueryBuilder;
import org.wikimedia.search.extra.levenshtein.LevenshteinDistanceScoreBuilder;
import org.wikimedia.search.extra.regex.SourceRegexQueryBuilder;
+import org.wikimedia.search.extra.router.DegradedRouterQueryBuilder;
import org.wikimedia.search.extra.router.TokenCountRouterQueryBuilder;
import org.wikimedia.search.extra.superdetectnoop.ChangeHandler;
import org.wikimedia.search.extra.superdetectnoop.SetHandler;
@@ -31,6 +34,14 @@
* Setup the Elasticsearch plugin.
*/
public class ExtraPlugin extends Plugin implements SearchPlugin,
AnalysisPlugin, ScriptPlugin {
+
+private OsService osService;
+
+public ExtraPlugin(Settings settings) {
+// TODO: This collects way more info than we care about
+osService = new OsService(settings);
+}
+
/**
* Register our parsers.
*/
@@ -40,7 +51,8 @@
return Arrays.asList(
new QuerySpec<>(SourceRegexQueryBuilder.NAME,
SourceRegexQueryBuilder::new, SourceRegexQueryBuilder::fromXContent),
new QuerySpec<>(FuzzyLikeThisQueryBuilder.NAME,
[MediaWiki-commits] [Gerrit] search/extra[master]: Add new Load Shedding Router
EBernhardson has uploaded a new change for review. (
https://gerrit.wikimedia.org/r/370778 )
Change subject: Add new Load Shedding Router
..
Add new Load Shedding Router
Add a new load shedding router than can decide on a query
to run based on load information about the local node. This
should help to ride out problems with less user visible
effect.
TODO (maybe later):
* Custom stats output about how many times it was triggered.
Unfortunately I havn't found any good way to hook into elasticsearch's
stats collection yet.
* Use the size of some thread pool queue as a trigger condition. Have
not investigated how viable this is.
* Use latency percentiles (p95, etc) as a trigger condition
Change-Id: I0abe91ccf2f628b03621a7f7f0fe634c52c039af
---
A docs/degraded_router.md
M src/main/java/org/wikimedia/search/extra/ExtraPlugin.java
M
src/main/java/org/wikimedia/search/extra/router/AbstractRouterQueryBuilder.java
A
src/main/java/org/wikimedia/search/extra/router/DegradedRouterQueryBuilder.java
M
src/main/java/org/wikimedia/search/extra/router/TokenCountRouterQueryBuilder.java
A
src/test/java/org/wikimedia/search/extra/router/DegradedRouterBuilderESTest.java
A
src/test/java/org/wikimedia/search/extra/router/DegradedRouterQueryBuilderParserTest.java
M
src/test/java/org/wikimedia/search/extra/router/TokenCountRouterBuilderESTest.java
M
src/test/java/org/wikimedia/search/extra/router/TokenCountRouterQueryIntegrationTest.java
9 files changed, 477 insertions(+), 16 deletions(-)
git pull ssh://gerrit.wikimedia.org:29418/search/extra
refs/changes/78/370778/1
diff --git a/docs/degraded_router.md b/docs/degraded_router.md
new file mode 100644
index 000..c727c2f
--- /dev/null
+++ b/docs/degraded_router.md
@@ -0,0 +1,48 @@
+degraded_router
+===
+
+The ```degraded_router``` is a simple query wrapper that allows
+routing queries based on the load of individual node. It's useful
+to prevent overloaded servers from having an outside effect on end
+user latency by running a cheaper query when the server is loaded.
+
+Example
+---
+
+GET /_search
+{
+"degraded_router": {
+"fallback": {
+"phrase_match": {
+"content": "what should we do today?",
+}
+}
+"conditions": [
+{
+"gte": 70,
+"type": "cpu",
+"query": {
+"match": {
+"content": "what should we do today?"
+}
+}
+}
+]
+}
+}
+
+A match query will be issued if system cpu usage is above 70%. Otherwise
+a phrase match query will be issued.
+
+Options
+---
+
+* `fallback` The query to apply if none of the conditions applies.
+* `conditions` Array of conditions (the first that matches wins):
+* `type`: The type of metric to compare against. Can be `cpu` for cpu%, or
+ `load`for 1 minute load average.
+* `predicate` : can be `eq`, `gt`, `gte`, `lt`, or `lte`, the value is the
number
+to compare against the value reported by `type`
+* `query` The query to apply if the condition is met.
+
+Note that the query parser does not check the conditions coherence
diff --git a/src/main/java/org/wikimedia/search/extra/ExtraPlugin.java
b/src/main/java/org/wikimedia/search/extra/ExtraPlugin.java
index acbb84f..e9ed04c 100644
--- a/src/main/java/org/wikimedia/search/extra/ExtraPlugin.java
+++ b/src/main/java/org/wikimedia/search/extra/ExtraPlugin.java
@@ -1,7 +1,10 @@
package org.wikimedia.search.extra;
+import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.index.IndexModule;
import org.elasticsearch.index.analysis.TokenFilterFactory;
import org.elasticsearch.indices.analysis.AnalysisModule.AnalysisProvider;
+import org.elasticsearch.monitor.os.OsService;
import org.elasticsearch.plugins.AnalysisPlugin;
import org.elasticsearch.plugins.Plugin;
import org.elasticsearch.plugins.ScriptPlugin;
@@ -17,7 +20,8 @@
import org.wikimedia.search.extra.superdetectnoop.VersionedDocumentHandler;
import org.wikimedia.search.extra.superdetectnoop.WithinAbsoluteHandler;
import org.wikimedia.search.extra.superdetectnoop.WithinPercentageHandler;
-import org.wikimedia.search.extra.tokencount.TokenCountRouterQueryBuilder;
+import org.wikimedia.search.extra.router.DegradedRouterQueryBuilder;
+import org.wikimedia.search.extra.router.TokenCountRouterQueryBuilder;
import java.util.Arrays;
import java.util.Collections;
@@ -31,6 +35,14 @@
* Setup the Elasticsearch plugin.
*/
public class ExtraPlugin extends Plugin implements SearchPlugin,
AnalysisPlugin, ScriptPlugin {
+
+OsService osService;
+
+public ExtraPlugin(Settings settings) {
+// TODO: This collects way more info than we care about
+osService = new OsService(settings);
+}
+
/**
* Register our parsers.
*/
@@ -40,7
