increase some file storage timeouts related to streams

lib/storage/file.js

@@ -14,6 +14,28 @@ const readFileBin = require("../stream-file").readFileBin;
 const BatchRead = require("../batch-read");
 
 const Schedule = require("../schedule");
+
+/*  Each time you write to a channel it will either use an open file descriptor
+    for that channel or open a new descriptor if one is not available. These are
+    automatically closed after this window to prevent a file descriptor leak, so
+    writes that take longer than this time may be dropped! */
+const CHANNEL_WRITE_WINDOW = 300000;
+
+/*  Each time you read a channel it will have this many milliseconds to complete
+    otherwise it will be closed to prevent a file descriptor leak. The server will
+    lock up if it uses all available file descriptors, so it's important to close
+    them. The tradeoff with this timeout is that some functions, the stream, and
+    and the timeout itself are stored in memory. A longer timeout uses more memory
+    and running out of memory will also kill the server. */
+const STREAM_CLOSE_TIMEOUT = 300000;
+
+/*  The above timeout closes the stream, but apparently that doesn't always work.
+    We set yet another timeout to allow the runtime to gracefully close the stream
+    (flushing all pending writes/reads and doing who knows what else). After this timeout
+    it will be MERCILESSLY DESTROYED. This isn't graceful, but again, file descriptor
+    leaks are bad. */
+const STREAM_DESTROY_TIMEOUT = 30000;
+
 const isValidChannelId = function (id) {
     return typeof(id) === 'string' &&
         id.length >= 32 && id.length < 50 &&
@@ -64,7 +86,7 @@ const destroyStream = function (stream) {
     try { stream.close(); } catch (err) { console.error(err); }
     setTimeout(function () {
         try { stream.destroy(); } catch (err) { console.error(err); }
-    }, 15000);
+    }, STREAM_DESTROY_TIMEOUT);
 };
 
 const ensureStreamCloses = function (stream, id, ms) {
@@ -74,7 +96,7 @@ const ensureStreamCloses = function (stream, id, ms) {
             // this can only be a timeout error...
             console.log("stream close error:", err, id);
         }
-    }), ms || 45000), []);
+    }), ms || STREAM_CLOSE_TIMEOUT), []);
 };
 
 // readMessagesBin asynchronously iterates over the messages in a channel log
@@ -729,7 +751,7 @@ var getChannel = function (env, id, _callback) {
                 delete env.channels[id];
                 destroyStream(channel.writeStream, path);
                 //console.log("closing writestream");
-            }, 120000);
+            }, CHANNEL_WRITE_WINDOW);
             channel.delayClose();
             env.channels[id] = channel;
             done(void 0, channel);