From: Art Cancro <ajc@citadel.org>
Date: Sun, 2 Jul 2017 04:46:53 +0000 (-0400)
Subject: Experiment with DB->compact() to reduce the size of database files on disk when possible.
X-Git-Tag: v939~534
X-Git-Url: https://code.citadel.org/?p=citadel.git;a=commitdiff_plain;h=dbee11a35d5d217f356279fa400d7f9deab86cb0

Experiment with DB->compact() to reduce the size of database files on disk when possible.
Commented out while we test it.
---

diff --git a/citadel/database.c b/citadel/database.c
index fcb82d2e5..4bd685d66 100644
--- a/citadel/database.c
+++ b/citadel/database.c
@@ -861,6 +861,25 @@ void cdb_trunc(int cdb)
 }
 
 
+/*
+ * compact (defragment) the database , possibly returning space back to the underlying filesystem
+ */
+void cdb_compact(void)
+{
+	int ret;
+	int i;
+
+	syslog(LOG_DEBUG, "db: cdb_compact() started");
+	for (i = 0; i < MAXCDB; i++) {
+		syslog(LOG_DEBUG, "db: compacting database %d", i);
+		ret = dbp[i]->compact(dbp[i], NULL, NULL, NULL, NULL, DB_FREE_SPACE, NULL);
+		if (ret) {
+			syslog(LOG_ERR, "db: compact: %s", db_strerror(ret));
+		}
+	}
+	syslog(LOG_DEBUG, "db: cdb_compact() finished");
+}
+
 
 // Has an item already been seen (is it in the CDB_USETABLE) ?
 // Returns 0 if it hasn't, 1 if it has
diff --git a/citadel/database.h b/citadel/database.h
index cfaa1bd60..b9b76b715 100644
--- a/citadel/database.h
+++ b/citadel/database.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1987-2012 by the citadel.org team
+ * Copyright (c) 1987-2017 by the citadel.org team
  *
  *  This program is open source software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License version 3.
@@ -34,6 +34,7 @@ void cdb_chmod_data(void);
 void cdb_checkpoint(void);
 void check_handles(void *arg);
 void cdb_cull_logs(void);
+void cdb_compact(void);
 
 
 /*
diff --git a/citadel/modules/expire/serv_expire.c b/citadel/modules/expire/serv_expire.c
index 5fce93473..7fd28e6b4 100644
--- a/citadel/modules/expire/serv_expire.c
+++ b/citadel/modules/expire/serv_expire.c
@@ -905,6 +905,13 @@ void purge_databases(void)
 	       	syslog(LOG_NOTICE, "Processed %d message reference count adjustments.", retval);
 	}
 
+	// Enable this after we've tested it and make it a site-configurable option.
+	// This will allow the database files to shrink when they can.
+	// if (!server_shutting_down)
+	// {
+		// cdb_compact();
+	// }
+
 	if (!server_shutting_down)
 	{
 	       	syslog(LOG_INFO, "Auto-purger: finished.");