Auto merge of #32695 - sfackler:default-buf-size, r=alexcrichton

bors · bors · commit 8694b4ffe9b2 · 2016-04-08T03:20:11.000-07:00
Drop the default buffer size to 8K The 64k capacity was picked by me a couple of years ago in the initial implementation of buffered IO adaptors: https://github.com/rust-lang/rust/pull/9091/files#diff-b131eeef531ad098b32f49695a031008R62. 64K was picked for symmetry with libuv, which we no longer use. 64K is *way* larger than the default size of any other language that I can find. C, C++, and Java default to 8K, and Go defaults to 4K. There have been a variety of issues filed relating to this such as #31885. Closes #31885
diff --git a/src/libstd/io/mod.rs b/src/libstd/io/mod.rs
@@ -292,7 +292,7 @@ mod lazy;
 mod util;
 mod stdio;
 
-const DEFAULT_BUF_SIZE: usize = 64 * 1024;
+const DEFAULT_BUF_SIZE: usize = 8 * 1024;
 
 // A few methods below (read_to_string, read_line) will append data into a
 // `String` buffer, but we need to be pretty careful when doing this. The
