From: Wido den Hollander <wido@42on.com>
Date: Tue, 16 Jun 2020 19:50:19 +0000 (+0200)
Subject: osd: Add config option to compact OSD's object store on start
X-Git-Tag: v16.1.0~1713^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=refs%2Fpull%2F35605%2Fhead;p=ceph.git

osd: Add config option to compact OSD's object store on start

By setting this configuration option an OSD will compact it's
store's OMAP on start.

This way admin's can trigger an offline compaction by setting this
configuration value to 'true' and then restarting the OSD.

This is easier than using tools like 'ceph-kvstore-tool' with requires
more manual work on the CLI and might be more difficult for users.

Signed-off-by: Wido den Hollander <wido@42on.com>
---

diff --git a/PendingReleaseNotes b/PendingReleaseNotes
index c487313ee4b3..b88f6001b8a8 100644
--- a/PendingReleaseNotes
+++ b/PendingReleaseNotes
@@ -92,3 +92,7 @@
     ceph fs required_client_features <fs name> add <feature>
     ceph fs required_client_features <fs name> rm <feature>
     ceph fs feature ls
+
+* OSD: A new configuration option ``osd_compact_on_start`` has been added which triggers
+  an OSD compaction on start. Setting this option to ``true`` and restarting an OSD
+  will result in an offline compaction of the OSD prior to booting.
diff --git a/src/common/options.cc b/src/common/options.cc
index 0d7c6880e9ed..3ff9807aca28 100644
--- a/src/common/options.cc
+++ b/src/common/options.cc
@@ -2514,6 +2514,10 @@ std::vector<Option> get_global_options() {
     .set_default(true)
     .set_description("flush FileStore journal contents during clean OSD shutdown"),
 
+    Option("osd_compact_on_start", Option::TYPE_BOOL, Option::LEVEL_ADVANCED)
+    .set_default(false)
+    .set_description("compact OSD's object store's OMAP on start"),
+
     Option("osd_os_flags", Option::TYPE_UINT, Option::LEVEL_DEV)
     .set_default(0)
     .set_description("flags to skip filestore omap or journal initialization"),
diff --git a/src/osd/OSD.cc b/src/osd/OSD.cc
index b1a0c70dda8f..ef1583a8ff4e 100644
--- a/src/osd/OSD.cc
+++ b/src/osd/OSD.cc
@@ -3500,6 +3500,10 @@ int OSD::init()
 
   dout(2) << "superblock: I am osd." << superblock.whoami << dendl;
 
+  if (cct->_conf.get_val<bool>("osd_compact_on_start")) {
+    dout(2) << "compacting object store's omap" << dendl;
+    store->compact();
+  }
 
   // prime osd stats
   {