Address Patrick's comments

Author: aarondav

docs/configuration.md

@@ -866,33 +866,15 @@ Apart from these, the following properties are also available, and may be useful
   <td>1</td>
   <td>
     (Netty only) Connections between hosts are reused in order to reduce connection buildup for 
-    large clusters. For small clusters with many hard disks, this may result in insufficient
+    large clusters. For clusters with many hard disks and few hosts, this may result in insufficient
     concurrency to saturate all disks, and so users may consider increasing this value.
   </td>
 </tr>
-<tr>
-  <td><code>spark.shuffle.io.serverThreads</code></td>
-  <td>min(num-cores, 8)</td>
-  <td>
-    (Netty only) Size of fixed pool of threads to make requests. As each thread gets 16 MB of 
-    off-heap buffer space initially, the default is limited to 8 cores to avoid excessive off-heap 
-    allocation. It has been experimentally determined that this default should be sufficient to 
-    saturate a 10Gb/s network, but in some cases this may have to be adjusted.
-  </td>
-</tr>
-<tr>
-  <td><code>spark.shuffle.io.clientThreads</code></td>
-  <td>min(num-cores, 8)</td>
-  <td>
-    (Netty only) Size of fixed pool of threads to make requests. This has the same properties as
-    <code>spark.shuffle.io.serverThreads</code>, above.
-  </td>
-</tr>
 <tr>
   <td><code>spark.shuffle.io.maxRetries</code></td>
   <td>3</td>
   <td>
-    (Netty only) Fetches that fail due to IO-related exceptions are automatically retried if this is 
+    (Netty only) Fetches that fail due to IO-related exceptions are automatically retried if this is
     set to a non-zero value. This retry logic helps stabilize large shuffles in the face of long GC 
     pauses or transient network connectivity issues.
   </td>