SERVER-33661 Constrain link parallelism for compile_all and compile_unittests

2 files changed, 57 insertions, 18 deletions

diff --git a/SConstruct b/SConstruct
index 5db0a7bef49..fa85da47db9 100644
--- a/SConstruct
+++ b/SConstruct
@@ -508,6 +508,11 @@ add_option('msvc-debugging-format',
     type='choice',
 )
 
+add_option('jlink',
+        help="Limit link concurrency to given value",
+        nargs=1,
+        type=int)
+
 try:
     with open("version.json", "r") as version_fp:
         version_data = json.load(version_fp)
@@ -3413,6 +3418,42 @@ env.Alias("distsrc-tgz", env.GZip(
 env.Alias("distsrc-zip", env.DistSrc("mongodb-src-${MONGO_VERSION}.zip"))
 env.Alias("distsrc", "distsrc-tgz")
 
+# Do this as close to last as possible before reading SConscripts, so
+# that any tools that may have injected other things via emitters are included
+# among the side effect adornments.
+#
+# TODO: Move this to a tool.
+if has_option('jlink'):
+    jlink = get_option('jlink')
+    if jlink < 1:
+        env.FatalError("The argument to jlink must be a positive integer")
+
+    target_builders = ['Program', 'SharedLibrary', 'LoadableModule']
+
+    # A bound map of stream (as in stream of work) name to side-effect
+    # file. Since SCons will not allow tasks with a shared side-effect
+    # to execute concurrently, this gives us a way to limit link jobs
+    # independently of overall SCons concurrency.
+    jlink_stream_map = dict()
+
+    def jlink_emitter(target, source, env):
+        name = str(target[0])
+        se_name = "#jlink-stream" + str(hash(name) % jlink)
+        se_node = jlink_stream_map.get(se_name, None)
+        if not se_node:
+            se_node = env.Entry(se_name)
+            # This may not be necessary, but why chance it
+            env.NoCache(se_node)
+            jlink_stream_map[se_name] = se_node
+        env.SideEffect(se_node, target)
+        return (target, source)
+
+    for target_builder in target_builders:
+        builder = env['BUILDERS'][target_builder]
+        base_emitter = builder.emitter
+        new_emitter = SCons.Builder.ListEmitter([base_emitter, jlink_emitter])
+        builder.emitter = new_emitter
+
 env.SConscript(
     dirs=[
         'src',
diff --git a/etc/evergreen.yml b/etc/evergreen.yml
index 6e281f018fe..2ea4d9bbdbd 100644
--- a/etc/evergreen.yml
+++ b/etc/evergreen.yml
@@ -969,9 +969,9 @@ functions:
         rm -rf ${install_directory|/data/mongo-install-directory}
 
         extra_args=""
-        if [ "${reduce_scons_compile_jobs_available|false}" = "true" ] && [ -n "${num_scons_compile_jobs_available|}" ]; then
-          echo "Changing SCons to run with --jobs=${num_scons_compile_jobs_available|}"
-          extra_args="$extra_args --jobs=${num_scons_compile_jobs_available|}"
+        if [ -n "${num_scons_link_jobs_available|}" ]; then
+          echo "Changing SCons to run with --jlink=${num_scons_link_jobs_available|}"
+          extra_args="$extra_args --jlink=${num_scons_link_jobs_available|}"
         fi
 
         ${activate_virtualenv}
@@ -2849,7 +2849,6 @@ tasks:
     - func: "scons compile"
       vars:
         targets: all
-        reduce_scons_compile_jobs_available: true
         task_compile_flags: >-
           --use-new-tools
           --build-mongoreplay="${build_mongoreplay}"
@@ -2872,7 +2871,6 @@ tasks:
     - func: "scons compile"
       vars:
         targets: unittests
-        reduce_scons_compile_jobs_available: true
         task_compile_flags: >-
           --detect-odr-violations
 
@@ -7622,7 +7620,7 @@ buildvariants:
     compile_flags: --ssl MONGO_DISTMOD=amazon2 --release -j$(grep -c ^processor /proc/cpuinfo) --variables-files=etc/scons/mongodbtoolchain_gcc.vars
     # We invoke SCons using --jobs = (# of CPUs / 4) to avoid causing out of memory errors due to
     # spawning a large number of linker processes.
-    num_scons_compile_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
+    num_scons_link_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
     num_jobs_available: $(grep -c ^processor /proc/cpuinfo)
     has_packages: true
     packager_script: packager_enterprise.py
@@ -7699,7 +7697,7 @@ buildvariants:
     compile_flags: --ssl MONGO_DISTMOD=amazon2 -j$(grep -c ^processor /proc/cpuinfo) --release --variables-files=etc/scons/mongodbtoolchain_gcc.vars
     # We invoke SCons using --jobs = (# of CPUs / 4) to avoid causing out of memory errors due to
     # spawning a large number of linker processes.
-    num_scons_compile_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
+    num_scons_link_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
     multiversion_platform: amazon
     multiversion_edition: targeted
     num_jobs_available: $(grep -c ^processor /proc/cpuinfo)
@@ -7798,7 +7796,7 @@ buildvariants:
     compile_flags: --dbg=on --opt=on --win-version-min=ws08r2 -j$(( $(grep -c ^processor /proc/cpuinfo) / 2 )) MONGO_DISTMOD=2008plus
     # We invoke SCons using --jobs = (# of CPUs / 4) to avoid causing out of memory errors due to
     # spawning a large number of linker processes.
-    num_scons_compile_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
+    num_scons_link_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
     python: python
     ext: zip
     use_scons_cache: true
@@ -7940,7 +7938,7 @@ buildvariants:
     compile_flags: --release --ssl MONGO_DISTMOD=windows-64 CPPPATH="c:/openssl/include c:/sasl/include c:/snmp/include c:/curl/include" LIBPATH="c:/openssl/lib c:/sasl/lib c:/snmp/lib c:/curl/lib" -j$(( $(grep -c ^processor /proc/cpuinfo) / 2 )) --dynamic-windows --win-version-min=ws08r2
     # We invoke SCons using --jobs = (# of CPUs / 4) to avoid causing out of memory errors due to
     # spawning a large number of linker processes.
-    num_scons_compile_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
+    num_scons_link_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
     python: python
     num_jobs_available: $(grep -c ^processor /proc/cpuinfo)
     ext: zip
@@ -8312,7 +8310,7 @@ buildvariants:
     compile_flags: --release --ssl MONGO_DISTMOD=windows-64 CPPPATH="c:/openssl/include c:/sasl/include c:/snmp/include c:/curl/include" LIBPATH="c:/openssl/lib c:/sasl/lib c:/snmp/lib c:/curl/lib" -j$(( $(grep -c ^processor /proc/cpuinfo) / 2 )) --dynamic-windows --win-version-min=ws08r2
     # We invoke SCons using --jobs = (# of CPUs / 4) to avoid causing out of memory errors due to
     # spawning a large number of linker processes.
-    num_scons_compile_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
+    num_scons_link_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
     python: python
     num_jobs_available: $(grep -c ^processor /proc/cpuinfo)
     ext: zip
@@ -8336,7 +8334,7 @@ buildvariants:
     compile_flags: --release --ssl --ssl-provider=openssl MONGO_DISTMOD=windows-64 CPPPATH="c:/openssl/include c:/sasl/include c:/snmp/include c:/curl/include" LIBPATH="c:/openssl/lib c:/sasl/lib c:/snmp/lib c:/curl/lib" -j$(( $(grep -c ^processor /proc/cpuinfo) / 2 )) --dynamic-windows --win-version-min=ws08r2
     # We invoke SCons using --jobs = (# of CPUs / 4) to avoid causing out of memory errors due to
     # spawning a large number of linker processes.
-    num_scons_compile_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
+    num_scons_link_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
     python: python
     num_jobs_available: $(grep -c ^processor /proc/cpuinfo)
     ext: zip
@@ -8365,7 +8363,7 @@ buildvariants:
     compile_flags: --release --ssl MONGO_DISTMOD=windows-64 CPPPATH="c:/openssl/include c:/sasl/include c:/snmp/include c:/curl/include" LIBPATH="c:/openssl/lib c:/sasl/lib c:/snmp/lib c:/curl/lib" -j$(( $(grep -c ^processor /proc/cpuinfo) / 2 )) --dynamic-windows --win-version-min=ws08r2
     # We invoke SCons using --jobs = (# of CPUs / 4) to avoid causing out of memory errors due to
     # spawning a large number of linker processes.
-    num_scons_compile_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
+    num_scons_link_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
     python: python
     num_jobs_available: $(grep -c ^processor /proc/cpuinfo)
     ext: zip
@@ -8401,7 +8399,7 @@ buildvariants:
     compile_flags: --release --ssl MONGO_DISTMOD=windows-64 CPPPATH="c:/openssl/include c:/sasl/include c:/snmp/include c:/curl/include" LIBPATH="c:/openssl/lib c:/sasl/lib c:/snmp/lib c:/curl/lib" -j$(( $(grep -c ^processor /proc/cpuinfo) / 2 )) --dynamic-windows --win-version-min=ws08r2
     # We invoke SCons using --jobs = (# of CPUs / 4) to avoid causing out of memory errors due to
     # spawning a large number of linker processes.
-    num_scons_compile_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
+    num_scons_link_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
     python: python
     num_jobs_available: $(grep -c ^processor /proc/cpuinfo)
     test_flags: --storageEngine=inMemory --excludeWithAnyTags=requires_persistence,requires_journaling,requires_mmapv1
@@ -8471,7 +8469,7 @@ buildvariants:
     compile_flags: --release --ssl MONGO_DISTMOD=2008plus-ssl CPPPATH="c:/openssl/include" LIBPATH="c:/openssl/lib" -j$(( $(grep -c ^processor /proc/cpuinfo) / 2 )) --dynamic-windows --win-version-min=ws08r2
     # We invoke SCons using --jobs = (# of CPUs / 4) to avoid causing out of memory errors due to
     # spawning a large number of linker processes.
-    num_scons_compile_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
+    num_scons_link_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
     python: python
     num_jobs_available: $(grep -c ^processor /proc/cpuinfo)
     ext: zip
@@ -8583,7 +8581,7 @@ buildvariants:
     compile_flags: --dbg=on --opt=off --ssl MONGO_DISTMOD=2008plus CPPPATH="c:/openssl/include c:/sasl/include c:/snmp/include c:/curl/include" LIBPATH="c:/openssl/lib c:/sasl/lib c:/snmp/lib c:/curl/lib" -j$(( $(grep -c ^processor /proc/cpuinfo) / 2 )) --dynamic-windows --win-version-min=ws08r2
     # We invoke SCons using --jobs = (# of CPUs / 4) to avoid causing out of memory errors due to
     # spawning a large number of linker processes.
-    num_scons_compile_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
+    num_scons_link_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
     python: python
     num_jobs_available: $(grep -c ^processor /proc/cpuinfo)
     ext: zip
@@ -11186,7 +11184,7 @@ buildvariants:
     compile_flags: --ssl MONGO_DISTMOD=debian92 --release -j$(grep -c ^processor /proc/cpuinfo) --variables-files=etc/scons/mongodbtoolchain_gcc.vars
     # We invoke SCons using --jobs = (# of CPUs / 4) to avoid causing out of memory errors due to
     # spawning a large number of linker processes.
-    num_scons_compile_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
+    num_scons_link_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
     num_jobs_available: $(grep -c ^processor /proc/cpuinfo)
     has_packages: true
     packager_script: packager_enterprise.py
@@ -11241,7 +11239,7 @@ buildvariants:
     compile_flags: --ssl MONGO_DISTMOD=debian92 -j$(grep -c ^processor /proc/cpuinfo) --release --variables-files=etc/scons/mongodbtoolchain_gcc.vars
     # We invoke SCons using --jobs = (# of CPUs / 4) to avoid causing out of memory errors due to
     # spawning a large number of linker processes.
-    num_scons_compile_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
+    num_scons_link_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
     multiversion_platform: debian92
     multiversion_edition: targeted
     num_jobs_available: $(grep -c ^processor /proc/cpuinfo)
@@ -12560,7 +12558,7 @@ buildvariants:
       c:/sasl/include c:/snmp/include c:/curl/include"  LIBPATH="c:/openssl/lib c:/sasl/lib
       c:/snmp/lib c:/curl/lib" -j$(( $(grep -c ^processor /proc/cpuinfo) / 2 )) --dynamic-windows
       --win-version-min=ws08r2
-    num_scons_compile_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
+    num_scons_link_jobs_available: $(( $(grep -c ^processor /proc/cpuinfo) / 4 ))
     python: python
     num_jobs_available: $(grep -c ^processor /proc/cpuinfo)
     ext: zip