tier/ctr: Solution for db locks for tier migrator and ctr using sqlite version less than 3.7 i.e rhel 6.7

Problem: On RHEL 6.7, we have sqlite version 3.6.2 which doesnt support
WAL journaling mode, as this journaling mode is only available in sqlite 3.7 and above.
As a result we cannot have to progreses concurrently accessing sqlite, without
running into db locks! Well WAL is also need for performace on CTR side.

Solution: This solution is to use CTR db connection for doing queries when WAL mode is
absent. i,e tier migrator will send sync_op ipc calls to CTR, which in turn will
do the query and create/update the query file suggested by tier migrator.

Pending: Well this solution will stop the db locks but the performance is still an issue for CTR.
We are developing an in-Memory Transaction Log (iMeTaL) which will help boost the CTR
performance by doing in memory udpates on the IO path and later flush the updates to
the db in a batch/segment flush.

Change-Id: Ie3149643ded159234b5cc6aa6cf93b9022c2f124
BUG: 1240577
Signed-off-by: Joseph Fernandes <josferna@redhat.com>
Signed-off-by: Dan Lambright <dlambrig@redhat.com>
Signed-off-by: Joseph Fernandes <josferna@redhat.com>
Reviewed-on: http://review.gluster.org/12191
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Luis Pabon <lpabon@redhat.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/xlators/features/changetimerecorder/src/ctr-helper.h b/xlators/features/changetimerecorder/src/ctr-helper.h
index cff7975660..dbad302946 100644
--- a/xlators/features/changetimerecorder/src/ctr-helper.h
+++ b/xlators/features/changetimerecorder/src/ctr-helper.h
@@ -30,6 +30,13 @@
 #define CTR_DEFAULT_HARDLINK_EXP_PERIOD 300  /* Five mins */
 #define CTR_DEFAULT_INODE_EXP_PERIOD    300 /* Five mins */
 
+
+typedef struct ctr_query_cbk_args {
+        FILE *queryFILE;
+        int count;
+} ctr_query_cbk_args_t;
+
+
 /*CTR Xlator Private structure*/
 typedef struct gf_ctr_private {
         gf_boolean_t                    enabled;