21223: Cast to int

[arvados.git] / services / fuse / arvados_fuse / command.py

diff --git a/services/fuse/arvados_fuse/command.py b/services/fuse/arvados_fuse/command.py
index 95b9a9773b044c8f4d5ba8e7a952747554822cc9..75ff4c132edb96ad40297935113aef243d2a6203 100644 (file)
--- a/services/fuse/arvados_fuse/command.py
+++ b/services/fuse/arvados_fuse/command.py
@@ -134,17 +134,31 @@ class Mount(object):
         if self.args.logfile:
             self.args.logfile = os.path.realpath(self.args.logfile)
 
+        try:
+            self._setup_logging()
+        except Exception as e:
+            self.logger.exception("arv-mount: exception during setup: %s", e)
+            exit(1)
+
         try:
             nofile_limit = resource.getrlimit(resource.RLIMIT_NOFILE)
-            if nofile_limit[0] < 10240:
-                resource.setrlimit(resource.RLIMIT_NOFILE, (min(10240, nofile_limit[1]), nofile_limit[1]))
+
+            minlimit = 10240
+            if self.args.file_cache:
+                # Adjust the file handle limit so it can meet
+                # the desired cache size. Multiply by 8 because the
+                # number of 64 MiB cache slots that keepclient
+                # allocates is RLIMIT_NOFILE / 8
+                minlimit = int((self.args.file_cache/(64*1024*1024)) * 8)
+
+            if nofile_limit[0] < minlimit:
+                resource.setrlimit(resource.RLIMIT_NOFILE, (min(minlimit, nofile_limit[1]), nofile_limit[1]))
         except Exception as e:
             self.logger.warning("arv-mount: unable to adjust file handle limit: %s", e)
 
-        self.logger.debug("arv-mount: file handle limit is %s", resource.getrlimit(resource.RLIMIT_NOFILE))
+        self.logger.info("arv-mount: RLIMIT_NOFILE is %s", resource.getrlimit(resource.RLIMIT_NOFILE))
 
         try:
-            self._setup_logging()
             self._setup_api()
             self._setup_mount()
         except Exception as e:
@@ -228,17 +242,28 @@ class Mount(object):
 
     def _setup_api(self):
         try:
+            # default value of file_cache is 0, this tells KeepBlockCache to
+            # choose a default based on whether disk_cache is enabled or not.
+
+            block_cache = arvados.keep.KeepBlockCache(cache_max=self.args.file_cache,
+                                                      disk_cache=self.args.disk_cache,
+                                                      disk_cache_dir=self.args.disk_cache_dir)
+
+            # If there's too many prefetch threads and you
+            # max out the CPU, delivering data to the FUSE
+            # layer actually ends up being slower.
+            # Experimentally, capping 7 threads seems to
+            # be a sweet spot.
+            prefetch_threads = min(max((block_cache.cache_max // (64 * 1024 * 1024)) - 1, 1), 7)
+
             self.api = arvados.safeapi.ThreadSafeApiCache(
                 apiconfig=arvados.config.settings(),
                 api_params={
                     'num_retries': self.args.retries,
                 },
-                # default value of file_cache is 0, this tells KeepBlockCache to
-                # choose a default based on whether disk_cache is enabled or not.
                 keep_params={
-                    'block_cache': arvados.keep.KeepBlockCache(cache_max=self.args.file_cache,
-                                                               disk_cache=self.args.disk_cache,
-                                                               disk_cache_dir=self.args.disk_cache_dir),
+                    'block_cache': block_cache,
+                    'num_prefetch_threads': prefetch_threads,
                     'num_retries': self.args.retries,
                 },
                 version='v1',