[gnome-builder] ctags: nice the ctags process

[Christian Hergert <chergert src gnome org>]

commit d60ffef23dba10e85774dd3211b961e39b9ed5dc
Author: Christian Hergert <chergert redhat com>
Date:   Mon Jun 25 21:33:02 2018 -0700

    ctags: nice the ctags process
    
    Anything we can do to reduce the priority here.
    
    It would be nice if we could cgroup things, but we don't really have that
    level of control.
    
    Unsure of what we can do on FreeBSD, but I presume that nice will work
    too (if someone can verify).

 src/plugins/ctags/ide-ctags-builder.c | 4 ++++
 1 file changed, 4 insertions(+)
---
diff --git a/src/plugins/ctags/ide-ctags-builder.c b/src/plugins/ctags/ide-ctags-builder.c
index 651703817..ede699395 100644
--- a/src/plugins/ctags/ide-ctags-builder.c
+++ b/src/plugins/ctags/ide-ctags-builder.c
@@ -140,6 +140,10 @@ ide_ctags_builder_build (IdeCtagsBuilder *self,
   ide_subprocess_launcher_setenv (launcher, "TMPDIR", cwd, TRUE);
   ide_subprocess_launcher_set_stdout_file_path (launcher, tags_path);
 
+#ifdef __linux__
+  ide_subprocess_launcher_push_argv (launcher, "nice");
+#endif
+
   ide_subprocess_launcher_push_argv (launcher, ctags);
   ide_subprocess_launcher_push_argv (launcher, "-f");
   ide_subprocess_launcher_push_argv (launcher, "-");