Add txn write conflict metrics

Signed-off-by: sujuntao <[email protected]>

Author: sujuntao

txnkv/transaction/pipelined_flush.go

@@ -34,6 +34,7 @@ import (
 	"github.com/tikv/client-go/v2/internal/locate"
 	"github.com/tikv/client-go/v2/internal/logutil"
 	"github.com/tikv/client-go/v2/kv"
+	"github.com/tikv/client-go/v2/metrics"
 	"github.com/tikv/client-go/v2/tikvrpc"
 	"github.com/tikv/client-go/v2/txnkv/rangetask"
 	"github.com/tikv/client-go/v2/txnkv/txnlock"
@@ -244,6 +245,7 @@ func (action actionPipelinedFlush) handleSingleBatch(
 			// TiKV will return a PessimisticLockNotFound error directly if it encounters a different lock. Otherwise,
 			// TiKV returns lock.TTL = 0, and we still need to resolve the lock.
 			if lock.TxnID > c.startTS && !c.isPessimistic {
+				metrics.LockResolverCountWithWriteConflict.Inc()
 				return tikverr.NewErrWriteConflictWithArgs(
 					c.startTS,
 					lock.TxnID,

txnkv/transaction/prewrite.go

@@ -487,6 +487,7 @@ func (handler *prewrite1BatchReqHandler) extractKeyErrs(keyErrs []*kvrpcpb.KeyEr
 		// TiKV returns lock.TTL = 0, and we still need to resolve the lock.
 		if (lock.TxnID > handler.committer.startTS && !handler.committer.isPessimistic) ||
 			handler.committer.txn.prewriteEncounterLockPolicy == NoResolvePolicy {
+			metrics.LockResolverCountWithWriteConflict.Inc()
 			return nil, tikverr.NewErrWriteConflictWithArgs(
 				handler.committer.startTS,
 				lock.TxnID,