Merge pull request #12896 from wilsonwang371/profiling-txn2

server: make applier use ReadTx() in Txn() instead of ConcurrentReadTx()

server/etcdmain/config.go

@@ -267,6 +267,7 @@ func newConfig() *config {
 	fs.DurationVar(&cfg.ec.ExperimentalDowngradeCheckTime, "experimental-downgrade-check-time", cfg.ec.ExperimentalDowngradeCheckTime, "Duration of time between two downgrade status check.")
 	fs.DurationVar(&cfg.ec.ExperimentalWarningApplyDuration, "experimental-warning-apply-duration", cfg.ec.ExperimentalWarningApplyDuration, "Time duration after which a warning is generated if request takes more time.")
 	fs.BoolVar(&cfg.ec.ExperimentalMemoryMlock, "experimental-memory-mlock", cfg.ec.ExperimentalMemoryMlock, "Enable to enforce etcd pages (in particular bbolt) to stay in RAM.")
+	fs.BoolVar(&cfg.ec.ExperimentalTxnModeWriteWithSharedBuffer, "experimental-txn-mode-write-with-shared-buffer", true, "Enable the write transaction to use a shared buffer in its readonly check operations.")
 
 	// unsafe
 	fs.BoolVar(&cfg.ec.UnsafeNoFsync, "unsafe-no-fsync", false, "Disables fsync, unsafe, will cause data loss.")

server/etcdmain/help.go

@@ -220,6 +220,8 @@ Experimental feature:
     Duration of periodical watch progress notification.
   --experimental-warning-apply-duration '100ms'
 	Warning is generated if requests take more than this duration.
+  --experimental-txn-mode-write-with-shared-buffer 'true'
+    Enable the write transaction to use a shared buffer in its readonly check operations.
 
 Unsafe feature:
   --force-new-cluster 'false'