Import wiredtiger: cc54220b06d23167290d9928a192f1c49769840d from branch mongodb-5.0

ref: bcb90a271c..cc54220b06
for: 5.0.0

WT-7281       Add metric to record total sessions scanned

7 files changed, 166 insertions, 152 deletions

diff --git a/src/third_party/wiredtiger/dist/stat_data.py b/src/third_party/wiredtiger/dist/stat_data.py
index 03ae93bb3e7..16cd9553968 100644
--- a/src/third_party/wiredtiger/dist/stat_data.py
+++ b/src/third_party/wiredtiger/dist/stat_data.py
@@ -559,6 +559,7 @@ connection_stats = [
     TxnStat('txn_rts_pages_visited', 'rollback to stable pages visited'),
     TxnStat('txn_rts_tree_walk_skip_pages', 'rollback to stable tree walk skipping pages'),
     TxnStat('txn_rts_upd_aborted', 'rollback to stable updates aborted'),
+    TxnStat('txn_sessions_walked', 'sessions scanned in each walk of concurrent sessions'),
     TxnStat('txn_set_ts', 'set timestamp calls'),
     TxnStat('txn_set_ts_durable', 'set timestamp durable calls'),
     TxnStat('txn_set_ts_durable_upd', 'set timestamp durable updates'),
diff --git a/src/third_party/wiredtiger/import.data b/src/third_party/wiredtiger/import.data
index 2207b8aad92..0a783ae3f7a 100644
--- a/src/third_party/wiredtiger/import.data
+++ b/src/third_party/wiredtiger/import.data
@@ -2,5 +2,5 @@
     "vendor": "wiredtiger",
     "github": "wiredtiger/wiredtiger.git",
     "branch": "mongodb-5.0",
-    "commit": "bcb90a271ce721d53ce49f1d805f52111f67a5e2"
+    "commit": "cc54220b06d23167290d9928a192f1c49769840d"
 }
diff --git a/src/third_party/wiredtiger/src/include/stat.h b/src/third_party/wiredtiger/src/include/stat.h
index 5dccf989a67..706e6fee492 100644
--- a/src/third_party/wiredtiger/src/include/stat.h
+++ b/src/third_party/wiredtiger/src/include/stat.h
@@ -634,6 +634,7 @@ struct __wt_connection_stats {
     int64_t txn_rts_pages_visited;
     int64_t txn_rts_tree_walk_skip_pages;
     int64_t txn_rts_upd_aborted;
+    int64_t txn_sessions_walked;
     int64_t txn_set_ts;
     int64_t txn_set_ts_durable;
     int64_t txn_set_ts_durable_upd;
diff --git a/src/third_party/wiredtiger/src/include/wiredtiger.in b/src/third_party/wiredtiger/src/include/wiredtiger.in
index 2c9da8cf4fa..fc45cf31e8d 100644
--- a/src/third_party/wiredtiger/src/include/wiredtiger.in
+++ b/src/third_party/wiredtiger/src/include/wiredtiger.in
@@ -5640,419 +5640,421 @@ extern int wiredtiger_extension_terminate(WT_CONNECTION *connection);
 #define	WT_STAT_CONN_TXN_RTS_TREE_WALK_SKIP_PAGES	1319
 /*! transaction: rollback to stable updates aborted */
 #define	WT_STAT_CONN_TXN_RTS_UPD_ABORTED		1320
+/*! transaction: sessions scanned in each walk of concurrent sessions */
+#define	WT_STAT_CONN_TXN_SESSIONS_WALKED		1321
 /*! transaction: set timestamp calls */
-#define	WT_STAT_CONN_TXN_SET_TS				1321
+#define	WT_STAT_CONN_TXN_SET_TS				1322
 /*! transaction: set timestamp durable calls */
-#define	WT_STAT_CONN_TXN_SET_TS_DURABLE			1322
+#define	WT_STAT_CONN_TXN_SET_TS_DURABLE			1323
 /*! transaction: set timestamp durable updates */
-#define	WT_STAT_CONN_TXN_SET_TS_DURABLE_UPD		1323
+#define	WT_STAT_CONN_TXN_SET_TS_DURABLE_UPD		1324
 /*! transaction: set timestamp oldest calls */
-#define	WT_STAT_CONN_TXN_SET_TS_OLDEST			1324
+#define	WT_STAT_CONN_TXN_SET_TS_OLDEST			1325
 /*! transaction: set timestamp oldest updates */
-#define	WT_STAT_CONN_TXN_SET_TS_OLDEST_UPD		1325
+#define	WT_STAT_CONN_TXN_SET_TS_OLDEST_UPD		1326
 /*! transaction: set timestamp stable calls */
-#define	WT_STAT_CONN_TXN_SET_TS_STABLE			1326
+#define	WT_STAT_CONN_TXN_SET_TS_STABLE			1327
 /*! transaction: set timestamp stable updates */
-#define	WT_STAT_CONN_TXN_SET_TS_STABLE_UPD		1327
+#define	WT_STAT_CONN_TXN_SET_TS_STABLE_UPD		1328
 /*! transaction: transaction begins */
-#define	WT_STAT_CONN_TXN_BEGIN				1328
+#define	WT_STAT_CONN_TXN_BEGIN				1329
 /*! transaction: transaction checkpoint currently running */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_RUNNING		1329
+#define	WT_STAT_CONN_TXN_CHECKPOINT_RUNNING		1330
 /*!
  * transaction: transaction checkpoint currently running for history
  * store file
  */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_RUNNING_HS		1330
+#define	WT_STAT_CONN_TXN_CHECKPOINT_RUNNING_HS		1331
 /*! transaction: transaction checkpoint generation */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_GENERATION		1331
+#define	WT_STAT_CONN_TXN_CHECKPOINT_GENERATION		1332
 /*!
  * transaction: transaction checkpoint history store file duration
  * (usecs)
  */
-#define	WT_STAT_CONN_TXN_HS_CKPT_DURATION		1332
+#define	WT_STAT_CONN_TXN_HS_CKPT_DURATION		1333
 /*! transaction: transaction checkpoint max time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_MAX		1333
+#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_MAX		1334
 /*! transaction: transaction checkpoint min time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_MIN		1334
+#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_MIN		1335
 /*!
  * transaction: transaction checkpoint most recent duration for gathering
  * all handles (usecs)
  */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_HANDLE_DURATION	1335
+#define	WT_STAT_CONN_TXN_CHECKPOINT_HANDLE_DURATION	1336
 /*!
  * transaction: transaction checkpoint most recent duration for gathering
  * applied handles (usecs)
  */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_HANDLE_DURATION_APPLY	1336
+#define	WT_STAT_CONN_TXN_CHECKPOINT_HANDLE_DURATION_APPLY	1337
 /*!
  * transaction: transaction checkpoint most recent duration for gathering
  * skipped handles (usecs)
  */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_HANDLE_DURATION_SKIP	1337
+#define	WT_STAT_CONN_TXN_CHECKPOINT_HANDLE_DURATION_SKIP	1338
 /*! transaction: transaction checkpoint most recent handles applied */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_HANDLE_APPLIED	1338
+#define	WT_STAT_CONN_TXN_CHECKPOINT_HANDLE_APPLIED	1339
 /*! transaction: transaction checkpoint most recent handles skipped */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_HANDLE_SKIPPED	1339
+#define	WT_STAT_CONN_TXN_CHECKPOINT_HANDLE_SKIPPED	1340
 /*! transaction: transaction checkpoint most recent handles walked */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_HANDLE_WALKED	1340
+#define	WT_STAT_CONN_TXN_CHECKPOINT_HANDLE_WALKED	1341
 /*! transaction: transaction checkpoint most recent time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_RECENT		1341
+#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_RECENT		1342
 /*! transaction: transaction checkpoint prepare currently running */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_PREP_RUNNING	1342
+#define	WT_STAT_CONN_TXN_CHECKPOINT_PREP_RUNNING	1343
 /*! transaction: transaction checkpoint prepare max time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_PREP_MAX		1343
+#define	WT_STAT_CONN_TXN_CHECKPOINT_PREP_MAX		1344
 /*! transaction: transaction checkpoint prepare min time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_PREP_MIN		1344
+#define	WT_STAT_CONN_TXN_CHECKPOINT_PREP_MIN		1345
 /*! transaction: transaction checkpoint prepare most recent time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_PREP_RECENT		1345
+#define	WT_STAT_CONN_TXN_CHECKPOINT_PREP_RECENT		1346
 /*! transaction: transaction checkpoint prepare total time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_PREP_TOTAL		1346
+#define	WT_STAT_CONN_TXN_CHECKPOINT_PREP_TOTAL		1347
 /*! transaction: transaction checkpoint scrub dirty target */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_SCRUB_TARGET	1347
+#define	WT_STAT_CONN_TXN_CHECKPOINT_SCRUB_TARGET	1348
 /*! transaction: transaction checkpoint scrub time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_SCRUB_TIME		1348
+#define	WT_STAT_CONN_TXN_CHECKPOINT_SCRUB_TIME		1349
 /*! transaction: transaction checkpoint total time (msecs) */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_TOTAL		1349
+#define	WT_STAT_CONN_TXN_CHECKPOINT_TIME_TOTAL		1350
 /*! transaction: transaction checkpoints */
-#define	WT_STAT_CONN_TXN_CHECKPOINT			1350
+#define	WT_STAT_CONN_TXN_CHECKPOINT			1351
 /*!
  * transaction: transaction checkpoints skipped because database was
  * clean
  */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_SKIPPED		1351
+#define	WT_STAT_CONN_TXN_CHECKPOINT_SKIPPED		1352
 /*! transaction: transaction failures due to history store */
-#define	WT_STAT_CONN_TXN_FAIL_CACHE			1352
+#define	WT_STAT_CONN_TXN_FAIL_CACHE			1353
 /*!
  * transaction: transaction fsync calls for checkpoint after allocating
  * the transaction ID
  */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_FSYNC_POST		1353
+#define	WT_STAT_CONN_TXN_CHECKPOINT_FSYNC_POST		1354
 /*!
  * transaction: transaction fsync duration for checkpoint after
  * allocating the transaction ID (usecs)
  */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_FSYNC_POST_DURATION	1354
+#define	WT_STAT_CONN_TXN_CHECKPOINT_FSYNC_POST_DURATION	1355
 /*! transaction: transaction range of IDs currently pinned */
-#define	WT_STAT_CONN_TXN_PINNED_RANGE			1355
+#define	WT_STAT_CONN_TXN_PINNED_RANGE			1356
 /*! transaction: transaction range of IDs currently pinned by a checkpoint */
-#define	WT_STAT_CONN_TXN_PINNED_CHECKPOINT_RANGE	1356
+#define	WT_STAT_CONN_TXN_PINNED_CHECKPOINT_RANGE	1357
 /*! transaction: transaction range of timestamps currently pinned */
-#define	WT_STAT_CONN_TXN_PINNED_TIMESTAMP		1357
+#define	WT_STAT_CONN_TXN_PINNED_TIMESTAMP		1358
 /*! transaction: transaction range of timestamps pinned by a checkpoint */
-#define	WT_STAT_CONN_TXN_PINNED_TIMESTAMP_CHECKPOINT	1358
+#define	WT_STAT_CONN_TXN_PINNED_TIMESTAMP_CHECKPOINT	1359
 /*!
  * transaction: transaction range of timestamps pinned by the oldest
  * active read timestamp
  */
-#define	WT_STAT_CONN_TXN_PINNED_TIMESTAMP_READER	1359
+#define	WT_STAT_CONN_TXN_PINNED_TIMESTAMP_READER	1360
 /*!
  * transaction: transaction range of timestamps pinned by the oldest
  * timestamp
  */
-#define	WT_STAT_CONN_TXN_PINNED_TIMESTAMP_OLDEST	1360
+#define	WT_STAT_CONN_TXN_PINNED_TIMESTAMP_OLDEST	1361
 /*! transaction: transaction read timestamp of the oldest active reader */
-#define	WT_STAT_CONN_TXN_TIMESTAMP_OLDEST_ACTIVE_READ	1361
+#define	WT_STAT_CONN_TXN_TIMESTAMP_OLDEST_ACTIVE_READ	1362
 /*! transaction: transaction rollback to stable currently running */
-#define	WT_STAT_CONN_TXN_ROLLBACK_TO_STABLE_RUNNING	1362
+#define	WT_STAT_CONN_TXN_ROLLBACK_TO_STABLE_RUNNING	1363
 /*! transaction: transaction sync calls */
-#define	WT_STAT_CONN_TXN_SYNC				1363
+#define	WT_STAT_CONN_TXN_SYNC				1364
 /*! transaction: transaction walk of concurrent sessions */
-#define	WT_STAT_CONN_TXN_WALK_SESSIONS			1364
+#define	WT_STAT_CONN_TXN_WALK_SESSIONS			1365
 /*! transaction: transactions committed */
-#define	WT_STAT_CONN_TXN_COMMIT				1365
+#define	WT_STAT_CONN_TXN_COMMIT				1366
 /*! transaction: transactions rolled back */
-#define	WT_STAT_CONN_TXN_ROLLBACK			1366
+#define	WT_STAT_CONN_TXN_ROLLBACK			1367
 /*! LSM: sleep for LSM checkpoint throttle */
-#define	WT_STAT_CONN_LSM_CHECKPOINT_THROTTLE		1367
+#define	WT_STAT_CONN_LSM_CHECKPOINT_THROTTLE		1368
 /*! LSM: sleep for LSM merge throttle */
-#define	WT_STAT_CONN_LSM_MERGE_THROTTLE			1368
+#define	WT_STAT_CONN_LSM_MERGE_THROTTLE			1369
 /*! cache: bytes currently in the cache */
-#define	WT_STAT_CONN_CACHE_BYTES_INUSE			1369
+#define	WT_STAT_CONN_CACHE_BYTES_INUSE			1370
 /*! cache: bytes dirty in the cache cumulative */
-#define	WT_STAT_CONN_CACHE_BYTES_DIRTY_TOTAL		1370
+#define	WT_STAT_CONN_CACHE_BYTES_DIRTY_TOTAL		1371
 /*! cache: bytes read into cache */
-#define	WT_STAT_CONN_CACHE_BYTES_READ			1371
+#define	WT_STAT_CONN_CACHE_BYTES_READ			1372
 /*! cache: bytes written from cache */
-#define	WT_STAT_CONN_CACHE_BYTES_WRITE			1372
+#define	WT_STAT_CONN_CACHE_BYTES_WRITE			1373
 /*! cache: checkpoint blocked page eviction */
-#define	WT_STAT_CONN_CACHE_EVICTION_CHECKPOINT		1373
+#define	WT_STAT_CONN_CACHE_EVICTION_CHECKPOINT		1374
 /*!
  * cache: checkpoint of history store file blocked non-history store page
  * eviction
  */
-#define	WT_STAT_CONN_CACHE_EVICTION_BLOCKED_CHECKPOINT_HS	1374
+#define	WT_STAT_CONN_CACHE_EVICTION_BLOCKED_CHECKPOINT_HS	1375
 /*! cache: eviction walk target pages histogram - 0-9 */
-#define	WT_STAT_CONN_CACHE_EVICTION_TARGET_PAGE_LT10	1375
+#define	WT_STAT_CONN_CACHE_EVICTION_TARGET_PAGE_LT10	1376
 /*! cache: eviction walk target pages histogram - 10-31 */
-#define	WT_STAT_CONN_CACHE_EVICTION_TARGET_PAGE_LT32	1376
+#define	WT_STAT_CONN_CACHE_EVICTION_TARGET_PAGE_LT32	1377
 /*! cache: eviction walk target pages histogram - 128 and higher */
-#define	WT_STAT_CONN_CACHE_EVICTION_TARGET_PAGE_GE128	1377
+#define	WT_STAT_CONN_CACHE_EVICTION_TARGET_PAGE_GE128	1378
 /*! cache: eviction walk target pages histogram - 32-63 */
-#define	WT_STAT_CONN_CACHE_EVICTION_TARGET_PAGE_LT64	1378
+#define	WT_STAT_CONN_CACHE_EVICTION_TARGET_PAGE_LT64	1379
 /*! cache: eviction walk target pages histogram - 64-128 */
-#define	WT_STAT_CONN_CACHE_EVICTION_TARGET_PAGE_LT128	1379
+#define	WT_STAT_CONN_CACHE_EVICTION_TARGET_PAGE_LT128	1380
 /*!
  * cache: eviction walk target pages reduced due to history store cache
  * pressure
  */
-#define	WT_STAT_CONN_CACHE_EVICTION_TARGET_PAGE_REDUCED	1380
+#define	WT_STAT_CONN_CACHE_EVICTION_TARGET_PAGE_REDUCED	1381
 /*! cache: eviction walks abandoned */
-#define	WT_STAT_CONN_CACHE_EVICTION_WALKS_ABANDONED	1381
+#define	WT_STAT_CONN_CACHE_EVICTION_WALKS_ABANDONED	1382
 /*! cache: eviction walks gave up because they restarted their walk twice */
-#define	WT_STAT_CONN_CACHE_EVICTION_WALKS_STOPPED	1382
+#define	WT_STAT_CONN_CACHE_EVICTION_WALKS_STOPPED	1383
 /*!
  * cache: eviction walks gave up because they saw too many pages and
  * found no candidates
  */
-#define	WT_STAT_CONN_CACHE_EVICTION_WALKS_GAVE_UP_NO_TARGETS	1383
+#define	WT_STAT_CONN_CACHE_EVICTION_WALKS_GAVE_UP_NO_TARGETS	1384
 /*!
  * cache: eviction walks gave up because they saw too many pages and
  * found too few candidates
  */
-#define	WT_STAT_CONN_CACHE_EVICTION_WALKS_GAVE_UP_RATIO	1384
+#define	WT_STAT_CONN_CACHE_EVICTION_WALKS_GAVE_UP_RATIO	1385
 /*! cache: eviction walks reached end of tree */
-#define	WT_STAT_CONN_CACHE_EVICTION_WALKS_ENDED		1385
+#define	WT_STAT_CONN_CACHE_EVICTION_WALKS_ENDED		1386
 /*! cache: eviction walks restarted */
-#define	WT_STAT_CONN_CACHE_EVICTION_WALK_RESTART	1386
+#define	WT_STAT_CONN_CACHE_EVICTION_WALK_RESTART	1387
 /*! cache: eviction walks started from root of tree */
-#define	WT_STAT_CONN_CACHE_EVICTION_WALK_FROM_ROOT	1387
+#define	WT_STAT_CONN_CACHE_EVICTION_WALK_FROM_ROOT	1388
 /*! cache: eviction walks started from saved location in tree */
-#define	WT_STAT_CONN_CACHE_EVICTION_WALK_SAVED_POS	1388
+#define	WT_STAT_CONN_CACHE_EVICTION_WALK_SAVED_POS	1389
 /*! cache: hazard pointer blocked page eviction */
-#define	WT_STAT_CONN_CACHE_EVICTION_HAZARD		1389
+#define	WT_STAT_CONN_CACHE_EVICTION_HAZARD		1390
 /*! cache: history store table insert calls */
-#define	WT_STAT_CONN_CACHE_HS_INSERT			1390
+#define	WT_STAT_CONN_CACHE_HS_INSERT			1391
 /*! cache: history store table insert calls that returned restart */
-#define	WT_STAT_CONN_CACHE_HS_INSERT_RESTART		1391
+#define	WT_STAT_CONN_CACHE_HS_INSERT_RESTART		1392
 /*!
  * cache: history store table out-of-order resolved updates that lose
  * their durable timestamp
  */
-#define	WT_STAT_CONN_CACHE_HS_ORDER_LOSE_DURABLE_TIMESTAMP	1392
+#define	WT_STAT_CONN_CACHE_HS_ORDER_LOSE_DURABLE_TIMESTAMP	1393
 /*!
  * cache: history store table out-of-order updates that were fixed up by
  * reinserting with the fixed timestamp
  */
-#define	WT_STAT_CONN_CACHE_HS_ORDER_REINSERT		1393
+#define	WT_STAT_CONN_CACHE_HS_ORDER_REINSERT		1394
 /*! cache: history store table reads */
-#define	WT_STAT_CONN_CACHE_HS_READ			1394
+#define	WT_STAT_CONN_CACHE_HS_READ			1395
 /*! cache: history store table reads missed */
-#define	WT_STAT_CONN_CACHE_HS_READ_MISS			1395
+#define	WT_STAT_CONN_CACHE_HS_READ_MISS			1396
 /*! cache: history store table reads requiring squashed modifies */
-#define	WT_STAT_CONN_CACHE_HS_READ_SQUASH		1396
+#define	WT_STAT_CONN_CACHE_HS_READ_SQUASH		1397
 /*!
  * cache: history store table truncation by rollback to stable to remove
  * an unstable update
  */
-#define	WT_STAT_CONN_CACHE_HS_KEY_TRUNCATE_RTS_UNSTABLE	1397
+#define	WT_STAT_CONN_CACHE_HS_KEY_TRUNCATE_RTS_UNSTABLE	1398
 /*!
  * cache: history store table truncation by rollback to stable to remove
  * an update
  */
-#define	WT_STAT_CONN_CACHE_HS_KEY_TRUNCATE_RTS		1398
+#define	WT_STAT_CONN_CACHE_HS_KEY_TRUNCATE_RTS		1399
 /*! cache: history store table truncation to remove an update */
-#define	WT_STAT_CONN_CACHE_HS_KEY_TRUNCATE		1399
+#define	WT_STAT_CONN_CACHE_HS_KEY_TRUNCATE		1400
 /*!
  * cache: history store table truncation to remove range of updates due
  * to key being removed from the data page during reconciliation
  */
-#define	WT_STAT_CONN_CACHE_HS_KEY_TRUNCATE_ONPAGE_REMOVAL	1400
+#define	WT_STAT_CONN_CACHE_HS_KEY_TRUNCATE_ONPAGE_REMOVAL	1401
 /*!
  * cache: history store table truncation to remove range of updates due
  * to out-of-order timestamp update on data page
  */
-#define	WT_STAT_CONN_CACHE_HS_ORDER_REMOVE		1401
+#define	WT_STAT_CONN_CACHE_HS_ORDER_REMOVE		1402
 /*! cache: history store table writes requiring squashed modifies */
-#define	WT_STAT_CONN_CACHE_HS_WRITE_SQUASH		1402
+#define	WT_STAT_CONN_CACHE_HS_WRITE_SQUASH		1403
 /*! cache: in-memory page passed criteria to be split */
-#define	WT_STAT_CONN_CACHE_INMEM_SPLITTABLE		1403
+#define	WT_STAT_CONN_CACHE_INMEM_SPLITTABLE		1404
 /*! cache: in-memory page splits */
-#define	WT_STAT_CONN_CACHE_INMEM_SPLIT			1404
+#define	WT_STAT_CONN_CACHE_INMEM_SPLIT			1405
 /*! cache: internal pages evicted */
-#define	WT_STAT_CONN_CACHE_EVICTION_INTERNAL		1405
+#define	WT_STAT_CONN_CACHE_EVICTION_INTERNAL		1406
 /*! cache: internal pages split during eviction */
-#define	WT_STAT_CONN_CACHE_EVICTION_SPLIT_INTERNAL	1406
+#define	WT_STAT_CONN_CACHE_EVICTION_SPLIT_INTERNAL	1407
 /*! cache: leaf pages split during eviction */
-#define	WT_STAT_CONN_CACHE_EVICTION_SPLIT_LEAF		1407
+#define	WT_STAT_CONN_CACHE_EVICTION_SPLIT_LEAF		1408
 /*! cache: modified pages evicted */
-#define	WT_STAT_CONN_CACHE_EVICTION_DIRTY		1408
+#define	WT_STAT_CONN_CACHE_EVICTION_DIRTY		1409
 /*! cache: overflow pages read into cache */
-#define	WT_STAT_CONN_CACHE_READ_OVERFLOW		1409
+#define	WT_STAT_CONN_CACHE_READ_OVERFLOW		1410
 /*! cache: page split during eviction deepened the tree */
-#define	WT_STAT_CONN_CACHE_EVICTION_DEEPEN		1410
+#define	WT_STAT_CONN_CACHE_EVICTION_DEEPEN		1411
 /*! cache: page written requiring history store records */
-#define	WT_STAT_CONN_CACHE_WRITE_HS			1411
+#define	WT_STAT_CONN_CACHE_WRITE_HS			1412
 /*! cache: pages read into cache */
-#define	WT_STAT_CONN_CACHE_READ				1412
+#define	WT_STAT_CONN_CACHE_READ				1413
 /*! cache: pages read into cache after truncate */
-#define	WT_STAT_CONN_CACHE_READ_DELETED			1413
+#define	WT_STAT_CONN_CACHE_READ_DELETED			1414
 /*! cache: pages read into cache after truncate in prepare state */
-#define	WT_STAT_CONN_CACHE_READ_DELETED_PREPARED	1414
+#define	WT_STAT_CONN_CACHE_READ_DELETED_PREPARED	1415
 /*! cache: pages requested from the cache */
-#define	WT_STAT_CONN_CACHE_PAGES_REQUESTED		1415
+#define	WT_STAT_CONN_CACHE_PAGES_REQUESTED		1416
 /*! cache: pages seen by eviction walk */
-#define	WT_STAT_CONN_CACHE_EVICTION_PAGES_SEEN		1416
+#define	WT_STAT_CONN_CACHE_EVICTION_PAGES_SEEN		1417
 /*! cache: pages written from cache */
-#define	WT_STAT_CONN_CACHE_WRITE			1417
+#define	WT_STAT_CONN_CACHE_WRITE			1418
 /*! cache: pages written requiring in-memory restoration */
-#define	WT_STAT_CONN_CACHE_WRITE_RESTORE		1418
+#define	WT_STAT_CONN_CACHE_WRITE_RESTORE		1419
 /*! cache: tracked dirty bytes in the cache */
-#define	WT_STAT_CONN_CACHE_BYTES_DIRTY			1419
+#define	WT_STAT_CONN_CACHE_BYTES_DIRTY			1420
 /*! cache: unmodified pages evicted */
-#define	WT_STAT_CONN_CACHE_EVICTION_CLEAN		1420
+#define	WT_STAT_CONN_CACHE_EVICTION_CLEAN		1421
 /*! checkpoint-cleanup: pages added for eviction */
-#define	WT_STAT_CONN_CC_PAGES_EVICT			1421
+#define	WT_STAT_CONN_CC_PAGES_EVICT			1422
 /*! checkpoint-cleanup: pages removed */
-#define	WT_STAT_CONN_CC_PAGES_REMOVED			1422
+#define	WT_STAT_CONN_CC_PAGES_REMOVED			1423
 /*! checkpoint-cleanup: pages skipped during tree walk */
-#define	WT_STAT_CONN_CC_PAGES_WALK_SKIPPED		1423
+#define	WT_STAT_CONN_CC_PAGES_WALK_SKIPPED		1424
 /*! checkpoint-cleanup: pages visited */
-#define	WT_STAT_CONN_CC_PAGES_VISITED			1424
+#define	WT_STAT_CONN_CC_PAGES_VISITED			1425
 /*! cursor: Total number of entries skipped by cursor next calls */
-#define	WT_STAT_CONN_CURSOR_NEXT_SKIP_TOTAL		1425
+#define	WT_STAT_CONN_CURSOR_NEXT_SKIP_TOTAL		1426
 /*! cursor: Total number of entries skipped by cursor prev calls */
-#define	WT_STAT_CONN_CURSOR_PREV_SKIP_TOTAL		1426
+#define	WT_STAT_CONN_CURSOR_PREV_SKIP_TOTAL		1427
 /*!
  * cursor: Total number of entries skipped to position the history store
  * cursor
  */
-#define	WT_STAT_CONN_CURSOR_SKIP_HS_CUR_POSITION	1427
+#define	WT_STAT_CONN_CURSOR_SKIP_HS_CUR_POSITION	1428
 /*!
  * cursor: cursor next calls that skip due to a globally visible history
  * store tombstone
  */
-#define	WT_STAT_CONN_CURSOR_NEXT_HS_TOMBSTONE		1428
+#define	WT_STAT_CONN_CURSOR_NEXT_HS_TOMBSTONE		1429
 /*!
  * cursor: cursor next calls that skip greater than or equal to 100
  * entries
  */
-#define	WT_STAT_CONN_CURSOR_NEXT_SKIP_GE_100		1429
+#define	WT_STAT_CONN_CURSOR_NEXT_SKIP_GE_100		1430
 /*! cursor: cursor next calls that skip less than 100 entries */
-#define	WT_STAT_CONN_CURSOR_NEXT_SKIP_LT_100		1430
+#define	WT_STAT_CONN_CURSOR_NEXT_SKIP_LT_100		1431
 /*!
  * cursor: cursor prev calls that skip due to a globally visible history
  * store tombstone
  */
-#define	WT_STAT_CONN_CURSOR_PREV_HS_TOMBSTONE		1431
+#define	WT_STAT_CONN_CURSOR_PREV_HS_TOMBSTONE		1432
 /*!
  * cursor: cursor prev calls that skip greater than or equal to 100
  * entries
  */
-#define	WT_STAT_CONN_CURSOR_PREV_SKIP_GE_100		1432
+#define	WT_STAT_CONN_CURSOR_PREV_SKIP_GE_100		1433
 /*! cursor: cursor prev calls that skip less than 100 entries */
-#define	WT_STAT_CONN_CURSOR_PREV_SKIP_LT_100		1433
+#define	WT_STAT_CONN_CURSOR_PREV_SKIP_LT_100		1434
 /*! cursor: open cursor count */
-#define	WT_STAT_CONN_CURSOR_OPEN_COUNT			1434
+#define	WT_STAT_CONN_CURSOR_OPEN_COUNT			1435
 /*! reconciliation: approximate byte size of timestamps in pages written */
-#define	WT_STAT_CONN_REC_TIME_WINDOW_BYTES_TS		1435
+#define	WT_STAT_CONN_REC_TIME_WINDOW_BYTES_TS		1436
 /*!
  * reconciliation: approximate byte size of transaction IDs in pages
  * written
  */
-#define	WT_STAT_CONN_REC_TIME_WINDOW_BYTES_TXN		1436
+#define	WT_STAT_CONN_REC_TIME_WINDOW_BYTES_TXN		1437
 /*! reconciliation: fast-path pages deleted */
-#define	WT_STAT_CONN_REC_PAGE_DELETE_FAST		1437
+#define	WT_STAT_CONN_REC_PAGE_DELETE_FAST		1438
 /*! reconciliation: page reconciliation calls */
-#define	WT_STAT_CONN_REC_PAGES				1438
+#define	WT_STAT_CONN_REC_PAGES				1439
 /*! reconciliation: page reconciliation calls for eviction */
-#define	WT_STAT_CONN_REC_PAGES_EVICTION			1439
+#define	WT_STAT_CONN_REC_PAGES_EVICTION			1440
 /*! reconciliation: pages deleted */
-#define	WT_STAT_CONN_REC_PAGE_DELETE			1440
+#define	WT_STAT_CONN_REC_PAGE_DELETE			1441
 /*!
  * reconciliation: pages written including an aggregated newest start
  * durable timestamp
  */
-#define	WT_STAT_CONN_REC_TIME_AGGR_NEWEST_START_DURABLE_TS	1441
+#define	WT_STAT_CONN_REC_TIME_AGGR_NEWEST_START_DURABLE_TS	1442
 /*!
  * reconciliation: pages written including an aggregated newest stop
  * durable timestamp
  */
-#define	WT_STAT_CONN_REC_TIME_AGGR_NEWEST_STOP_DURABLE_TS	1442
+#define	WT_STAT_CONN_REC_TIME_AGGR_NEWEST_STOP_DURABLE_TS	1443
 /*!
  * reconciliation: pages written including an aggregated newest stop
  * timestamp
  */
-#define	WT_STAT_CONN_REC_TIME_AGGR_NEWEST_STOP_TS	1443
+#define	WT_STAT_CONN_REC_TIME_AGGR_NEWEST_STOP_TS	1444
 /*!
  * reconciliation: pages written including an aggregated newest stop
  * transaction ID
  */
-#define	WT_STAT_CONN_REC_TIME_AGGR_NEWEST_STOP_TXN	1444
+#define	WT_STAT_CONN_REC_TIME_AGGR_NEWEST_STOP_TXN	1445
 /*!
  * reconciliation: pages written including an aggregated newest
  * transaction ID
  */
-#define	WT_STAT_CONN_REC_TIME_AGGR_NEWEST_TXN		1445
+#define	WT_STAT_CONN_REC_TIME_AGGR_NEWEST_TXN		1446
 /*!
  * reconciliation: pages written including an aggregated oldest start
  * timestamp
  */
-#define	WT_STAT_CONN_REC_TIME_AGGR_OLDEST_START_TS	1446
+#define	WT_STAT_CONN_REC_TIME_AGGR_OLDEST_START_TS	1447
 /*! reconciliation: pages written including an aggregated prepare */
-#define	WT_STAT_CONN_REC_TIME_AGGR_PREPARED		1447
+#define	WT_STAT_CONN_REC_TIME_AGGR_PREPARED		1448
 /*!
  * reconciliation: pages written including at least one start durable
  * timestamp
  */
-#define	WT_STAT_CONN_REC_TIME_WINDOW_PAGES_DURABLE_START_TS	1448
+#define	WT_STAT_CONN_REC_TIME_WINDOW_PAGES_DURABLE_START_TS	1449
 /*!
  * reconciliation: pages written including at least one start transaction
  * ID
  */
-#define	WT_STAT_CONN_REC_TIME_WINDOW_PAGES_START_TXN	1449
+#define	WT_STAT_CONN_REC_TIME_WINDOW_PAGES_START_TXN	1450
 /*!
  * reconciliation: pages written including at least one stop durable
  * timestamp
  */
-#define	WT_STAT_CONN_REC_TIME_WINDOW_PAGES_DURABLE_STOP_TS	1450
+#define	WT_STAT_CONN_REC_TIME_WINDOW_PAGES_DURABLE_STOP_TS	1451
 /*! reconciliation: pages written including at least one stop timestamp */
-#define	WT_STAT_CONN_REC_TIME_WINDOW_PAGES_STOP_TS	1451
+#define	WT_STAT_CONN_REC_TIME_WINDOW_PAGES_STOP_TS	1452
 /*!
  * reconciliation: pages written including at least one stop transaction
  * ID
  */
-#define	WT_STAT_CONN_REC_TIME_WINDOW_PAGES_STOP_TXN	1452
+#define	WT_STAT_CONN_REC_TIME_WINDOW_PAGES_STOP_TXN	1453
 /*! reconciliation: records written including a start durable timestamp */
-#define	WT_STAT_CONN_REC_TIME_WINDOW_DURABLE_START_TS	1453
+#define	WT_STAT_CONN_REC_TIME_WINDOW_DURABLE_START_TS	1454
 /*! reconciliation: records written including a start timestamp */
-#define	WT_STAT_CONN_REC_TIME_WINDOW_START_TS		1454
+#define	WT_STAT_CONN_REC_TIME_WINDOW_START_TS		1455
 /*! reconciliation: records written including a start transaction ID */
-#define	WT_STAT_CONN_REC_TIME_WINDOW_START_TXN		1455
+#define	WT_STAT_CONN_REC_TIME_WINDOW_START_TXN		1456
 /*! reconciliation: records written including a stop durable timestamp */
-#define	WT_STAT_CONN_REC_TIME_WINDOW_DURABLE_STOP_TS	1456
+#define	WT_STAT_CONN_REC_TIME_WINDOW_DURABLE_STOP_TS	1457
 /*! reconciliation: records written including a stop timestamp */
-#define	WT_STAT_CONN_REC_TIME_WINDOW_STOP_TS		1457
+#define	WT_STAT_CONN_REC_TIME_WINDOW_STOP_TS		1458
 /*! reconciliation: records written including a stop transaction ID */
-#define	WT_STAT_CONN_REC_TIME_WINDOW_STOP_TXN		1458
+#define	WT_STAT_CONN_REC_TIME_WINDOW_STOP_TXN		1459
 /*! session: tiered storage local retention time (secs) */
-#define	WT_STAT_CONN_TIERED_RETENTION			1459
+#define	WT_STAT_CONN_TIERED_RETENTION			1460
 /*! session: tiered storage object size */
-#define	WT_STAT_CONN_TIERED_OBJECT_SIZE			1460
+#define	WT_STAT_CONN_TIERED_OBJECT_SIZE			1461
 /*! transaction: race to read prepared update retry */
-#define	WT_STAT_CONN_TXN_READ_RACE_PREPARE_UPDATE	1461
+#define	WT_STAT_CONN_TXN_READ_RACE_PREPARE_UPDATE	1462
 /*!
  * transaction: rollback to stable history store records with stop
  * timestamps older than newer records
  */
-#define	WT_STAT_CONN_TXN_RTS_HS_STOP_OLDER_THAN_NEWER_START	1462
+#define	WT_STAT_CONN_TXN_RTS_HS_STOP_OLDER_THAN_NEWER_START	1463
 /*! transaction: rollback to stable inconsistent checkpoint */
-#define	WT_STAT_CONN_TXN_RTS_INCONSISTENT_CKPT		1463
+#define	WT_STAT_CONN_TXN_RTS_INCONSISTENT_CKPT		1464
 /*! transaction: rollback to stable keys removed */
-#define	WT_STAT_CONN_TXN_RTS_KEYS_REMOVED		1464
+#define	WT_STAT_CONN_TXN_RTS_KEYS_REMOVED		1465
 /*! transaction: rollback to stable keys restored */
-#define	WT_STAT_CONN_TXN_RTS_KEYS_RESTORED		1465
+#define	WT_STAT_CONN_TXN_RTS_KEYS_RESTORED		1466
 /*! transaction: rollback to stable restored tombstones from history store */
-#define	WT_STAT_CONN_TXN_RTS_HS_RESTORE_TOMBSTONES	1466
+#define	WT_STAT_CONN_TXN_RTS_HS_RESTORE_TOMBSTONES	1467
 /*! transaction: rollback to stable restored updates from history store */
-#define	WT_STAT_CONN_TXN_RTS_HS_RESTORE_UPDATES		1467
+#define	WT_STAT_CONN_TXN_RTS_HS_RESTORE_UPDATES		1468
 /*! transaction: rollback to stable sweeping history store keys */
-#define	WT_STAT_CONN_TXN_RTS_SWEEP_HS_KEYS		1468
+#define	WT_STAT_CONN_TXN_RTS_SWEEP_HS_KEYS		1469
 /*! transaction: rollback to stable updates removed from history store */
-#define	WT_STAT_CONN_TXN_RTS_HS_REMOVED			1469
+#define	WT_STAT_CONN_TXN_RTS_HS_REMOVED			1470
 /*! transaction: transaction checkpoints due to obsolete pages */
-#define	WT_STAT_CONN_TXN_CHECKPOINT_OBSOLETE_APPLIED	1470
+#define	WT_STAT_CONN_TXN_CHECKPOINT_OBSOLETE_APPLIED	1471
 /*! transaction: update conflicts */
-#define	WT_STAT_CONN_TXN_UPDATE_CONFLICT		1471
+#define	WT_STAT_CONN_TXN_UPDATE_CONFLICT		1472
 
 /*!
  * @}
diff --git a/src/third_party/wiredtiger/src/support/stat.c b/src/third_party/wiredtiger/src/support/stat.c
index 396249e69c7..73aadc87b42 100644
--- a/src/third_party/wiredtiger/src/support/stat.c
+++ b/src/third_party/wiredtiger/src/support/stat.c
@@ -1284,6 +1284,7 @@ static const char *const __stats_connection_desc[] = {
   "transaction: rollback to stable pages visited",
   "transaction: rollback to stable tree walk skipping pages",
   "transaction: rollback to stable updates aborted",
+  "transaction: sessions scanned in each walk of concurrent sessions",
   "transaction: set timestamp calls",
   "transaction: set timestamp durable calls",
   "transaction: set timestamp durable updates",
@@ -1801,6 +1802,7 @@ __wt_stat_connection_clear_single(WT_CONNECTION_STATS *stats)
     stats->txn_rts_pages_visited = 0;
     stats->txn_rts_tree_walk_skip_pages = 0;
     stats->txn_rts_upd_aborted = 0;
+    stats->txn_sessions_walked = 0;
     stats->txn_set_ts = 0;
     stats->txn_set_ts_durable = 0;
     stats->txn_set_ts_durable_upd = 0;
@@ -2310,6 +2312,7 @@ __wt_stat_connection_aggregate(WT_CONNECTION_STATS **from, WT_CONNECTION_STATS *
     to->txn_rts_pages_visited += WT_STAT_READ(from, txn_rts_pages_visited);
     to->txn_rts_tree_walk_skip_pages += WT_STAT_READ(from, txn_rts_tree_walk_skip_pages);
     to->txn_rts_upd_aborted += WT_STAT_READ(from, txn_rts_upd_aborted);
+    to->txn_sessions_walked += WT_STAT_READ(from, txn_sessions_walked);
     to->txn_set_ts += WT_STAT_READ(from, txn_set_ts);
     to->txn_set_ts_durable += WT_STAT_READ(from, txn_set_ts_durable);
     to->txn_set_ts_durable_upd += WT_STAT_READ(from, txn_set_ts_durable_upd);
diff --git a/src/third_party/wiredtiger/src/txn/txn.c b/src/third_party/wiredtiger/src/txn/txn.c
index fd856c35bdb..bbefea1d64c 100644
--- a/src/third_party/wiredtiger/src/txn/txn.c
+++ b/src/third_party/wiredtiger/src/txn/txn.c
@@ -171,6 +171,7 @@ __wt_txn_active(WT_SESSION_IMPL *session, uint64_t txnid)
     WT_ORDERED_READ(session_cnt, conn->session_cnt);
     WT_STAT_CONN_INCR(session, txn_walk_sessions);
     for (i = 0, s = txn_global->txn_shared_list; i < session_cnt; i++, s++) {
+        WT_STAT_CONN_INCR(session, txn_sessions_walked);
         /* If the transaction is in the list, it is uncommitted. */
         if (s->id == txnid)
             goto done;
@@ -243,6 +244,7 @@ __txn_get_snapshot_int(WT_SESSION_IMPL *session, bool publish)
     WT_ORDERED_READ(session_cnt, conn->session_cnt);
     WT_STAT_CONN_INCR(session, txn_walk_sessions);
     for (i = 0, s = txn_global->txn_shared_list; i < session_cnt; i++, s++) {
+        WT_STAT_CONN_INCR(session, txn_sessions_walked);
         /*
          * Build our snapshot of any concurrent transaction IDs.
          *
@@ -344,6 +346,7 @@ __txn_oldest_scan(WT_SESSION_IMPL *session, uint64_t *oldest_idp, uint64_t *last
     WT_ORDERED_READ(session_cnt, conn->session_cnt);
     WT_STAT_CONN_INCR(session, txn_walk_sessions);
     for (i = 0, s = txn_global->txn_shared_list; i < session_cnt; i++, s++) {
+        WT_STAT_CONN_INCR(session, txn_sessions_walked);
         /* Update the last running transaction ID. */
         while ((id = s->id) != WT_TXN_NONE && WT_TXNID_LE(prev_oldest_id, id) &&
           WT_TXNID_LT(id, last_running)) {
@@ -2315,6 +2318,7 @@ __wt_verbose_dump_txn(WT_SESSION_IMPL *session)
      */
     WT_STAT_CONN_INCR(session, txn_walk_sessions);
     for (i = 0, s = txn_global->txn_shared_list; i < session_cnt; i++, s++) {
+        WT_STAT_CONN_INCR(session, txn_sessions_walked);
         /* Skip sessions with no active transaction */
         if ((id = s->id) == WT_TXN_NONE && s->pinned_id == WT_TXN_NONE)
             continue;
diff --git a/src/third_party/wiredtiger/src/txn/txn_timestamp.c b/src/third_party/wiredtiger/src/txn/txn_timestamp.c
index 6b046373187..6acd265fd2d 100644
--- a/src/third_party/wiredtiger/src/txn/txn_timestamp.c
+++ b/src/third_party/wiredtiger/src/txn/txn_timestamp.c
@@ -113,6 +113,7 @@ __wt_txn_get_pinned_timestamp(WT_SESSION_IMPL *session, wt_timestamp_t *tsp, uin
     WT_ORDERED_READ(session_cnt, conn->session_cnt);
     WT_STAT_CONN_INCR(session, txn_walk_sessions);
     for (i = 0, s = txn_global->txn_shared_list; i < session_cnt; i++, s++) {
+        WT_STAT_CONN_INCR(session, txn_sessions_walked);
         __txn_get_read_timestamp(s, &tmp_read_ts);
         /*
          * A zero timestamp is possible here only when the oldest timestamp is not accounted for.
@@ -172,6 +173,7 @@ __txn_global_query_timestamp(WT_SESSION_IMPL *session, wt_timestamp_t *tsp, cons
         WT_ORDERED_READ(session_cnt, conn->session_cnt);
         WT_STAT_CONN_INCR(session, txn_walk_sessions);
         for (i = 0, s = txn_global->txn_shared_list; i < session_cnt; i++, s++) {
+            WT_STAT_CONN_INCR(session, txn_sessions_walked);
             __txn_get_durable_timestamp(s, &tmpts);
             if (tmpts != WT_TS_NONE && --tmpts < ts)
                 ts = tmpts;
@@ -504,6 +506,7 @@ __txn_assert_after_reads(WT_SESSION_IMPL *session, const char *op, wt_timestamp_
     WT_ORDERED_READ(session_cnt, S2C(session)->session_cnt);
     WT_STAT_CONN_INCR(session, txn_walk_sessions);
     for (i = 0, s = txn_global->txn_shared_list; i < session_cnt; i++, s++) {
+        WT_STAT_CONN_INCR(session, txn_sessions_walked);
         __txn_get_read_timestamp(s, &tmp_timestamp);
         if (tmp_timestamp != WT_TS_NONE && tmp_timestamp >= ts) {
             __wt_readunlock(session, &txn_global->rwlock);