diff --git a/oam/etc/Columnstore.xml b/oam/etc/Columnstore.xml
index 0de06e10d9..e1da34bd40 100644
--- a/oam/etc/Columnstore.xml
+++ b/oam/etc/Columnstore.xml
@@ -154,8 +154,7 @@
 		<!-- The percentage of RAM to use for the disk block cache. Defaults to 70% -->
 		<!-- Alternatively, this can be specified in absolute terms using
 		     the suffixes 'm' or 'g' to denote size in megabytes or gigabytes.-->
-		<!-- <NumBlocksPct>95</NumBlocksPct> -->
-		<!-- <NumThreads>16</NumThreads> --> <!-- 1-256.  Default is 16. -->
+		<!-- <NumThreads>16</NumThreads> --> <!-- 1-256.  Default is CPU cores number. -->
 		<NumCaches>1</NumCaches><!-- # of parallel caches to instantiate -->
 		<IOMTracing>0</IOMTracing>
 		<BRPTracing>0</BRPTracing>
@@ -163,7 +162,7 @@
 		<MaxOpenFiles>2K</MaxOpenFiles>
 		<DecreaseOpenFilesCount>200</DecreaseOpenFilesCount>
 		<FDCacheTrace>0</FDCacheTrace>
-		<NumBlocksPct>50</NumBlocksPct>
+		<NumBlocksPct>20</NumBlocksPct>
 	</DBBC>
 	<Installation>
 		<ServerTypeInstall>2</ServerTypeInstall>
@@ -186,7 +185,7 @@
 		<MaxBuckets>128</MaxBuckets>
 		<MaxElems>128K</MaxElems>  <!-- 128 buckets * 128K * 16 = 256 MB -->
 		<PmMaxMemorySmallSide>1G</PmMaxMemorySmallSide>
-		<TotalUmMemory>25%</TotalUmMemory>
+		<TotalUmMemory>65%</TotalUmMemory>
 		<CPUniqueLimit>100</CPUniqueLimit>
 		<AllowDiskBasedJoin>N</AllowDiskBasedJoin>
 		<TempFileCompression>Y</TempFileCompression>