diff --git a/src/main/scala/service/ActivityService.scala b/src/main/scala/service/ActivityService.scala
index 50d0b0d..b607488 100644
--- a/src/main/scala/service/ActivityService.scala
+++ b/src/main/scala/service/ActivityService.scala
@@ -141,7 +141,13 @@
   def insertCommitId(userName: String, repositoryName: String, commitId: String) = {
     CommitLog insert (userName, repositoryName, commitId)
   }
-  
+
+  def insertAllCommitIds(userName: String, repositoryName: String, commitIds: List[String]) =
+    CommitLog insertAll (commitIds.map(commitId => (userName, repositoryName, commitId)): _*)
+
+  def getAllCommitIds(userName: String, repositoryName: String): List[String] =
+    Query(CommitLog).filter(_.byRepository(userName, repositoryName)).map(_.commitId).list
+
   def existsCommitId(userName: String, repositoryName: String, commitId: String): Boolean =
     Query(CommitLog).filter(_.byPrimaryKey(userName, repositoryName, commitId)).firstOption.isDefined
   
diff --git a/src/main/scala/servlet/GitRepositoryServlet.scala b/src/main/scala/servlet/GitRepositoryServlet.scala
index f7b2172..5718e46 100644
--- a/src/main/scala/servlet/GitRepositoryServlet.scala
+++ b/src/main/scala/servlet/GitRepositoryServlet.scala
@@ -15,6 +15,7 @@
 import service._
 import WebHookService._
 import org.eclipse.jgit.api.Git
+import util.JGitUtil.CommitInfo
 
 /**
  * Provides Git repository via HTTP.
@@ -87,19 +88,26 @@
         val commits = JGitUtil.getCommitLog(git, command.getOldId.name, command.getNewId.name)
         val refName = command.getRefName.split("/")
         
-        // apply issue comment
-        val newCommits = commits.flatMap { commit =>
-          if(!existsCommitId(owner, repository, commit.id)){
-            insertCommitId(owner, repository, commit.id)
-            "(^|\\W)#(\\d+)(\\W|$)".r.findAllIn(commit.fullMessage).matchData.foreach { matchData =>
-              val issueId = matchData.group(2)
-              if(getAccountByUserName(commit.committer).isDefined && getIssue(owner, repository, issueId).isDefined){
-                createComment(owner, repository, commit.committer, issueId.toInt, commit.fullMessage, "commit")
-              }
+        // Extract new commit and apply issue comment
+        val newCommits = if(commits.size > 1000){
+          val existIds = getAllCommitIds(owner, repository)
+          commits.flatMap { commit =>
+            optionIf(!existIds.contains(commit.id)){
+              createIssueComment(commit)
+              Some(commit)
             }
-            Some(commit)
-          } else None
-        }.toList
+          }
+        } else {
+          commits.flatMap { commit =>
+            optionIf(!existsCommitId(owner, repository, commit.id)){
+              createIssueComment(commit)
+              Some(commit)
+            }
+          }
+        }
+
+        // batch insert all new commit id
+        insertAllCommitIds(owner, repository, newCommits.map(_.id))
         
         // record activity
         if(refName(1) == "heads"){
@@ -132,4 +140,14 @@
     // update repository last modified time.
     updateLastActivityDate(owner, repository)
   }
+
+  private def createIssueComment(commit: CommitInfo) = {
+    "(^|\\W)#(\\d+)(\\W|$)".r.findAllIn(commit.fullMessage).matchData.foreach { matchData =>
+      val issueId = matchData.group(2)
+      if(getAccountByUserName(commit.committer).isDefined && getIssue(owner, repository, issueId).isDefined){
+        createComment(owner, repository, commit.committer, issueId.toInt, commit.fullMessage, "commit")
+      }
+    }
+  }
+
 }