From 198030fadfbc3849f004deb8bb9108d0a0fad19a Mon Sep 17 00:00:00 2001 From: Alex Crichton Date: Tue, 2 Sep 2014 18:39:19 -0700 Subject: [PATCH] std: Turn down the stdout chunk size I've found that 64k is still too much and continue to see the errors as reported in #14940. I've locally found that 32k fails, and 24k succeeds, so I've trimmed the size down to 8192 which libuv happens to use as well. It sounds like the limit can still be hit with many threads in play, but I have yet to reproduce this, so I figure we can wait until that's hit (if it's possible) and then take action. --- src/libstd/io/stdio.rs | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/src/libstd/io/stdio.rs b/src/libstd/io/stdio.rs index fea161c426a..9315ff12ca3 100644 --- a/src/libstd/io/stdio.rs +++ b/src/libstd/io/stdio.rs @@ -362,7 +362,14 @@ impl Writer for StdWriter { // sizes. For an example, see #14940. For this reason, chunk the output // buffer on windows, but on unix we can just write the whole buffer all // at once. - let max_size = if cfg!(windows) {64 * 1024} else {uint::MAX}; + // + // For some other references, it appears that this problem has been + // encountered by others [1] [2]. We choose the number 8KB just because + // libuv does the same. + // + // [1]: https://tahoe-lafs.org/trac/tahoe-lafs/ticket/1232 + // [2]: http://www.mail-archive.com/log4net-dev@logging.apache.org/msg00661.html + let max_size = if cfg!(windows) {8192} else {uint::MAX}; for chunk in buf.chunks(max_size) { try!(match self.inner { TTY(ref mut tty) => tty.write(chunk),