Due to slow build time of android, we turn on ccache and make parallel build (make -j 24) to speed up the 2nd build. However, ccache storage would occupy almost 5G data (No compress). If the configuration of ccache size is less than 5G, then some task would clear the folder but other task would like to generate the dep/obj files on ccache, it produce the FATAL Error message as following:
ccache: FATAL: Could not create /proj/user/.ccache/d/9/0d33b843b730a552f8ea38387a3a02-1515162.o.tmp.stdout.my_server.3448 (permission denied?)

Our work around solution is to add retry mechanism while error happened. Do it have smart solution ?

diff -du ccache-3.1.8/ccache.c original_code/ccache-3.1.8/ccache.c
--- ccache-3.1.8/ccache.c       2012-10-09 17:11:47.280689370 +0800
+++ original_code/ccache-3.1.8/ccache.c 2012-08-11 17:03:17.000000000 +0800
@@ -519,11 +519,9 @@
 static void
 to_cache(struct args *args)
 {
-       unsigned to_sleep = 1000; /* Microseconds. */
        char *tmp_stdout, *tmp_stderr, *tmp_obj;
        struct stat st;
        int status;
-       int retry_times;
        size_t added_bytes = 0;
        unsigned added_files = 0;

@@ -550,30 +548,11 @@

        cc_log("Running real compiler");
        status = execute(args->argv, tmp_stdout, tmp_stderr);
-       if (stat(tmp_stdout, &st) != 0) {
-               retry_times++;
-               cc_log("FATAL_ERROR %d:build argv = %s, tmp_stdout=%s, tmp_stderr=%s,error_string=%s",retry_times,*args->argv, tmp_stdout, tmp_stderr,strerror(errno));
-               /* Retry after sleep to_sleep, we guest it is because of the ccache size over the config and recyline issues*/
-               usleep(to_sleep);
-               status = execute(args->argv, tmp_stdout, tmp_stderr);
-               if (stat(tmp_stdout, &st) != 0) {
-                       retry_times++;
-                       cc_log("FATAL_ERROR %d:build argv = %s, tmp_stdout=%s, tmp_stderr=%s,error_string=%s",retry_times,*args->argv, tmp_stdout, tmp_stderr,strerror(errno));
-                       usleep(to_sleep);
-                       status = execute(args->argv, tmp_stdout, tmp_stderr);
-                       if (stat(tmp_stdout, &st) != 0) {
-                               retry_times++;
-                               cc_log("FATAL_ERROR %d:build argv = %s, tmp_stdout=%s, tmp_stderr=%s,error_string=%s",retry_times,*args->argv, tmp_stdout, tmp_stderr,strerror(errno));
-                               usleep(to_sleep);
-                               status = execute(args->argv, tmp_stdout, tmp_stderr);
-                               if (stat(tmp_stdout, &st) != 0) {
-                                       fatal("Could not create %s (permission denied?)", tmp_stdout);
-                               }
-                       }
-               }
-       }
        args_pop(args, 3);

+       if (stat(tmp_stdout, &st) != 0) {
+               fatal("Could not create %s (permission denied?)", tmp_stdout);
+       }
        if (st.st_size != 0) {
                cc_log("Compiler produced stdout");
                stats_update(STATS_STDOUT);