Index: src/os_unix.c
==================================================================
--- src/os_unix.c
+++ src/os_unix.c
@@ -207,10 +207,14 @@
   unixInodeInfo *pInode;              /* Info about locks on this inode */
   int h;                              /* The file descriptor */
   unsigned char eFileLock;            /* The type of lock held on this fd */
   unsigned short int ctrlFlags;       /* Behavioral bits.  UNIXFILE_* flags */
   int lastErrno;                      /* The unix errno from last I/O error */
+#ifdef SQLITE_WRITE_QUEUE_FLUSH_HACK
+  unsigned int nUnsyncWrite;          /* Bytes written since last fsync() */
+  unsigned int nUnsyncLimit;          /* Maximum bytes written before fsync() */
+#endif
   void *lockingContext;               /* Locking style specific state */
   UnixUnusedFd *pPreallocatedUnused;  /* Pre-allocated UnixUnusedFd */
   const char *zPath;                  /* Name of the file */
   unixShm *pShm;                      /* Shared memory segment information */
   int szChunk;                        /* Configured by FCNTL_CHUNK_SIZE */
@@ -3366,11 +3370,22 @@
       offset += nCopy;
     }
   }
 #endif
  
-  while( (wrote = seekAndWrite(pFile, offset, pBuf, amt))<amt && wrote>0 ){
+  while( 1 ){
+    wrote = seekAndWrite(pFile, offset, pBuf, amt);
+#ifdef SQLITE_WRITE_QUEUE_FLUSH_HACK
+    if( pFile->nUnsyncLimit ){
+      pFile->nUnsyncWrite += wrote;
+      if( pFile->nUnsyncWrite>=pFile->nUnsyncLimit ){
+        fdatasync(pFile->h);
+        pFile->nUnsyncWrite = 0;
+      }
+    }
+#endif
+    if( wrote>=amt || wrote<=0 ) break;
     amt -= wrote;
     offset += wrote;
     pBuf = &((char*)pBuf)[wrote];
   }
   SimulateIOError(( wrote=(-1), amt=1 ));
@@ -3595,10 +3610,13 @@
   SimulateDiskfullError( return SQLITE_FULL );
 
   assert( pFile );
   OSTRACE(("SYNC    %-3d\n", pFile->h));
   rc = full_fsync(pFile->h, isFullsync, isDataOnly);
+#ifdef SQLITE_WRITE_QUEUE_FLUSH_HACK
+  pFile->nUnsyncWrite = 0;
+#endif
   SimulateIOError( rc=1 );
   if( rc ){
     storeLastErrno(pFile, errno);
     return unixLogError(SQLITE_IOERR_FSYNC, "full_fsync", pFile->zPath);
   }
@@ -3815,10 +3833,21 @@
     case SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE: {
       int rc = osIoctl(pFile->h, F2FS_IOC_ABORT_VOLATILE_WRITE);
       return rc ? SQLITE_IOERR_ROLLBACK_ATOMIC : SQLITE_OK;
     }
 #endif /* __linux__ && SQLITE_ENABLE_BATCH_ATOMIC_WRITE */
+
+#ifdef SQLITE_WRITE_QUEUE_FLUSH_HACK
+    case SQLITE_FCNTL_PRAGMA: {
+      char **azParam = (char**)pArg;
+      if( sqlite3_stricmp(azParam[1],"fsync_interval")==0 ){
+        pFile->nUnsyncLimit = atoi(azParam[2]);
+        return SQLITE_OK;
+      }
+      return SQLITE_NOTFOUND;
+    }
+#endif
 
     case SQLITE_FCNTL_LOCKSTATE: {
       *(int*)pArg = pFile->eFileLock;
       return SQLITE_OK;
     }