Add section on compressing pexe files for deployment.

native_client_sdk/src/doc/devguide/devcycle/building.rst

Index: native_client_sdk/src/doc/devguide/devcycle/building.rst
diff --git a/native_client_sdk/src/doc/devguide/devcycle/building.rst b/native_client_sdk/src/doc/devguide/devcycle/building.rst
index 3344293d9f35e17262d4ac238f19b8ba8a9497a9..167af6fe007a492c5da08a6c2e172c4556cc3a70 100644
--- a/native_client_sdk/src/doc/devguide/devcycle/building.rst
+++ b/native_client_sdk/src/doc/devguide/devcycle/building.rst
@@ -161,6 +161,8 @@ pnacl-clang
   C compiler and compiler driver
 pnacl-clang++
   C++ compiler and compiler driver
+pnacl-compress
+  Size compresses a finalized **pexe** file for deployment.
 pnacl-dis
   Disassembler for both **pexe** files and **nexe** files
 pnacl-finalize
@@ -324,6 +326,33 @@ The ``create_nmf.py`` tool helps generate an ``.nmf`` file, but ``.nmf``
 files can also be written by hand.
 
 
+
+Compressing the **pexe** for deployment
+---------------------------------------
+
+Size compression is an optional step for deployment, and reduces the
+size of the pexe file that must be transmitted over the wire. The tool
+pnacl-compress applies compression strategies that are already built

[jvoung (off chromium), 2014/02/26 18:01:04]

Some of the tool names are formatted with "``" around them. E.g.,
``x86_64-nacl-gcc`` below and ``pnacl-clang++`` above.

[Karl, 2014/02/27 18:37:27]

Done.

+into the **stable** binary format of a pexe application. As such,
+compressed pexe files do not need any extra time to be decompressed on
+the client's side. All costs are upfront when you call pnacl-compress.

[jvoung (off chromium), 2014/02/26 18:01:04]

Might be worth mentioning that it doesn't replace gzip. The effects stack a bit.

size(foo.gzip) - size(foo.pnacl-compressed.gzip) > 0

a couple of pexes I checked -- python ~7.8%, amiga emulator 4%, dragons 9.5%,
some other pexe 9.4%...

[Karl, 2014/02/27 18:37:27]

Added paragraph for this.

+
+Currently, this tool will compress pexe files by about 25%. However,
+it is somewhat slow (can take from seconds to minutes on large
+appications). Hence, this step is optional.
+
+.. naclcode::
+  :prettyprint: 0
+
+  <NACL_SDK_ROOT>/toolchain/win_pnacl/bin/pnacl-compress ^
+    hello_world.final.pexe
+
+Tool pncl-compress must be called after a pexe file has been finalized

[JF, 2014/02/26 17:27:21]

s/pncl/pnacl/

[Karl, 2014/02/27 18:37:27]

Done.

+for deployment (via pnacl-finalize). Alternatively, you can apply this
+step as part of the finalizing step by adding the ``--compress`` flag
+to the pnacl-finalize command line.
+
+
 The GNU-based toolchains
 ========================