Author: frm
Date: Tue Oct 4 16:45:05 2016
New Revision: 1763299
URL: http://svn.apache.org/viewvc?rev=1763299&view=rev
Log:
OAK-4886 - Don't load segments if they are already available locally
Modified:
jackrabbit/oak/trunk/oak-segment-tar/src/main/java/org/apache/jackrabbit/oak/segment/standby/client/StandbyClientSyncExecution.java
Modified:
jackrabbit/oak/trunk/oak-segment-tar/src/main/java/org/apache/jackrabbit/oak/segment/standby/client/StandbyClientSyncExecution.java
URL:
http://svn.apache.org/viewvc/jackrabbit/oak/trunk/oak-segment-tar/src/main/java/org/apache/jackrabbit/oak/segment/standby/client/StandbyClientSyncExecution.java?rev=1763299&r1=1763298&r2=1763299&view=diff
==============================================================================
---
jackrabbit/oak/trunk/oak-segment-tar/src/main/java/org/apache/jackrabbit/oak/segment/standby/client/StandbyClientSyncExecution.java
(original)
+++
jackrabbit/oak/trunk/oak-segment-tar/src/main/java/org/apache/jackrabbit/oak/segment/standby/client/StandbyClientSyncExecution.java
Tue Oct 4 16:45:05 2016
@@ -58,6 +58,8 @@ class StandbyClientSyncExecution {
private final Set<UUID> queued = newHashSet();
+ private final Set<UUID> local = newHashSet();
+
private final Map<UUID, Segment> cache = newHashMap();
StandbyClientSyncExecution(FileStore store, StandbyClient client,
Supplier<Boolean> running) {
@@ -146,6 +148,25 @@ class StandbyClientSyncExecution {
continue;
}
+ // Short circuit for the "sharing-is-caring problem". If many
+ // new segments are sharing segments that are already locally
+ // available, we should not issue a request for it to the
+ // server.
+
+ if (local.contains(referenced)) {
+ continue;
+ }
+
+ if (isLocal(referenced)) {
+ local.add(referenced);
+ continue;
+ }
+
+ // If we arrive at this point, the referenced segment is 1) not
+ // present locally, 2) not already queued for retrieval and 3)
+ // never visited before. We can safely add the reference to the
+ // queue and transfer the segment later.
+
log.debug("Found reference from {} to {}", current,
referenced);
if
(SegmentId.isDataSegmentId(referenced.getLeastSignificantBits())) {
@@ -159,6 +180,23 @@ class StandbyClientSyncExecution {
}
}
+ private boolean isLocal(UUID id) {
+ SegmentId referencedId = store.newSegmentId(
+ id.getMostSignificantBits(),
+ id.getLeastSignificantBits()
+ );
+
+ boolean persisted = true;
+
+ try {
+ referencedId.getSegment();
+ } catch(SegmentNotFoundException e) {
+ persisted = false;
+ }
+
+ return persisted;
+ }
+
private Segment copySegmentFromPrimary(UUID uuid) throws Exception {
Segment result = cache.get(uuid);
