From 280795800594ba7f4762a35188d875eacf3b6e9d Mon Sep 17 00:00:00 2001
From: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Date: Tue, 1 Oct 2019 10:48:20 +0200
Subject: [PATCH] dcap: restart pool selection on OUT-OF-DATE error

Motivation:
As pool selection is a probabilistic, two write transfers might hit the
same pool. If there are no sufficient space, pool will reject to start a
mover with OUT-OF-DATE error. Though, this is a transient error and a new
pool can be selected, dcap door propagates error to the client application.

Modification:
Threat OUT-OF-DATE as a transient error and restart pool selection.

Result:
dcap door can handle out-of-date errors

Acked-by: Marina Sahakyan
Target: master, 6.0, 5.2, 5.1, 4.2
Require-book: no
Require-notes: yes
(cherry picked from commit 87ae552206265549113970db9245eb19df0d1d6e)
Signed-off-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
---
 .../doors/DCapDoorInterpreterV3.java          | 34 ++++++++++---------
 1 file changed, 18 insertions(+), 16 deletions(-)

diff --git a/modules/dcache-dcap/src/main/java/diskCacheV111/doors/DCapDoorInterpreterV3.java b/modules/dcache-dcap/src/main/java/diskCacheV111/doors/DCapDoorInterpreterV3.java
index 33950f60e18..d52592c1395 100644
--- a/modules/dcache-dcap/src/main/java/diskCacheV111/doors/DCapDoorInterpreterV3.java
+++ b/modules/dcache-dcap/src/main/java/diskCacheV111/doors/DCapDoorInterpreterV3.java
@@ -2194,24 +2194,26 @@ private void storeChecksumInPnfs( PnfsId pnfsId , String checksumString){
         poolIoFileArrived( PoolIoFileMessage reply ){
 
             _log.debug("poolIoFileArrived : {}", reply);
-            if( reply.getReturnCode() != 0 ){
-                // bad entry in cacheInfo and pool Manager did not check it ( for performance reason )
-                // try again
-                if (reply.getReturnCode() == CacheException.FILE_NOT_IN_REPOSITORY) {
+            switch (reply.getReturnCode()) {
+                case 0:
+                    _moverId = reply.getMoverId();
+                    //
+                    // nothing to do here ( we are still waiting for
+                    //   doorTransferFinished )
+                    //
+                    setStatus("WaitingForDoorTransferOk");
+                    break;
+                case CacheException.FILE_NOT_IN_REPOSITORY:
+                    // fallthrough
+                case CacheException.OUT_OF_DATE:
+                    // transient errors
+                    _log.warn("Retry on transient error: {}", reply.getReturnCode());
                     again(true);
-                    return;
-                }
-
-                sendReply("poolIoFileArrived", reply);
-                removeUs();
-                return;
+                    break;
+                default:
+                    sendReply("poolIoFileArrived", reply);
+                    removeUs();
             }
-            _moverId = reply.getMoverId();
-            //
-            // nothing to do here ( we are still waiting for
-            //   doorTransferFinished )
-            //
-            setStatus( "WaitingForDoorTransferOk" ) ;
         }
 
         public void poolPassiveIoFileMessage( PoolPassiveIoFileMessage<byte[]> reply) {