diff options
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/virtiofsd/helper.c | 26 |
1 files changed, 25 insertions, 1 deletions
diff --git a/tools/virtiofsd/helper.c b/tools/virtiofsd/helper.c index dc59f38af0..00a1ef666a 100644 --- a/tools/virtiofsd/helper.c +++ b/tools/virtiofsd/helper.c @@ -176,7 +176,8 @@ void fuse_cmdline_help(void) " default: no_xattr\n" " --rlimit-nofile=<num> set maximum number of file descriptors\n" " (0 leaves rlimit unchanged)\n" - " default: 1,000,000 if the current rlimit is lower\n" + " default: min(1000000, fs.file-max - 16384)\n" + " if the current rlimit is lower\n" ); } @@ -199,9 +200,32 @@ static int fuse_helper_opt_proc(void *data, const char *arg, int key, static unsigned long get_default_rlimit_nofile(void) { + g_autofree gchar *file_max_str = NULL; + const rlim_t reserved_fds = 16384; /* leave at least this many fds free */ rlim_t max_fds = 1000000; /* our default RLIMIT_NOFILE target */ + rlim_t file_max; struct rlimit rlim; + /* + * Reduce max_fds below the system-wide maximum, if necessary. This + * ensures there are fds available for other processes so we don't + * cause resource exhaustion. + */ + if (!g_file_get_contents("/proc/sys/fs/file-max", &file_max_str, + NULL, NULL)) { + fuse_log(FUSE_LOG_ERR, "can't read /proc/sys/fs/file-max\n"); + exit(1); + } + file_max = g_ascii_strtoull(file_max_str, NULL, 10); + if (file_max < 2 * reserved_fds) { + fuse_log(FUSE_LOG_ERR, + "The fs.file-max sysctl is too low (%lu) to allow a " + "reasonable number of open files.\n", + (unsigned long)file_max); + exit(1); + } + max_fds = MIN(file_max - reserved_fds, max_fds); + if (getrlimit(RLIMIT_NOFILE, &rlim) < 0) { fuse_log(FUSE_LOG_ERR, "getrlimit(RLIMIT_NOFILE): %m\n"); exit(1); |