README.md: Add note about default do_cmake.sh debug builds.

Signed-off-by: Mark Nelson <mnelson@redhat.com>

diff --git a/README.md b/README.md
index 27ce841d0177d276fae0e0e709d1b4a90ab3cf8f..49b6a6957b96be9424b2479e9c7b19c4e9b44f8c 100644 (file)
--- a/README.md
+++ b/README.md
@@ -59,6 +59,11 @@ Build instructions:
        cd build
        make
 
+(Note: do_cmake.sh now defaults to creating a debug build of ceph that can
+be up to 5x slower with some workloads. Please pass 
+"-DCMAKE_BUILD_TYPE=RelWithDebInfo" to do_cmake.sh to create a non-debug 
+release.)
+
 This assumes you make your build dir a subdirectory of the ceph.git
 checkout. If you put it elsewhere, just replace `..` in do_cmake.sh with a
 correct path to the checkout. Any additional CMake args can be specified