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doc/go1.3.html: Performance, plus some library details

LGTM=dvyukov, iant, rsc
R=golang-codereviews, dvyukov, iant, rsc
CC=golang-codereviews
https://golang.org/cl/85250043
This commit is contained in:
Rob Pike 2014-04-09 07:12:20 +10:00
parent 9610b616c6
commit 969dc7626b

View File

@ -92,6 +92,8 @@ liveness (TODO what to say)
<p>
TODO compiler/linker boundary moved
TODO: liblink: pull linker i/o into separate liblink C library (CL 35790044)
</p>
<p>
@ -124,36 +126,68 @@ cmd/go: cover -atomic for -race (CL 76370043)
<h2 id="performance">Performance</h2>
<p>
TODO
The performance of Go binaries for this release has improved in many cases due to changes
in the runtime and garbage collection, plus some changes to libraries.
Significant instances include:
</p>
<ul>
<li>
TODO
As mentioned above, the default stack size has been reduced from 8 kilobytes to 4 kilobytes.
</li>
<li>
The runtime handles defers more efficiently, reducing the memory footprint by about two kilobytes
per goroutine that calls defer.
</li>
<li>
The garbage collector has been sped up, using a concurrent sweep algorithm,
better parallelization, and larger pages.
The cumulative effect can be a 50-70% reduction in collector pause time.
</li>
<li>
The race detector (see <a href="http://golang.org/doc/articles/race_detector.html">this guide</a>)
is now about 40% faster.
</li>
<li>
The regular expression package <a href="/pkg/regexp/"><code>regexp</code></a>
is now significantly faster for certain simple expressions due to the implemenation of
a second, one-pass execution engine. The choice of which engine to use is automatic;
the details are hidden from the user.
</li>
</ul>
<p>
Also, the runtime now includes in stack dumps how long a goroutine has been blocked,
which can be useful information when debugging deadlocks or performance issues.
</p>
<h2 id="library">Changes to the standard library</h2>
<p>
TODO: Which should be called out?
</p>
<p>
There is an important new type added to the standard library: <a href="/pkg/sync/pool/"><code>sync/pool</code></a>.
TODO: sync: add Pool (CL 41860043, 46010043)
</p>
<h3 id="new_packages">New packages</h3>
<p>
No new packages appear in the core libraries in Go 1.3.
</p>
<h3 id="major_library_changes">Major changes to the library</h3>
<p>
There is an important new type added to the standard library: <a href="/pkg/sync/#Pool"><code>sync.Pool</code></a>.
It provides an efficient mechanism for implementing certain types of caches whose memory
can be reclaimed automatically by the system.
</p>
<p>
TODO: crypto/tls: ServerName or InsecureSkipVerify (CL 67010043)
possible breaking change
</p>
<h3 id="minor_library_changes">Minor changes to the library</h3>
<p>
@ -163,34 +197,72 @@ See the relevant package documentation for more information about each change.
<ul>
<li> TODO: cmplx.Pow(0, x): https://codereview.appspot.com/76940044</li>
<li> TODO: crypto/tls: ServerName or InsecureSkipVerify (CL 67010043)</li>
<li>
The complex power function, <a href="/pkg/math/cmplx/#Pow"><code>Pow</code></a>,
now specifies the behavior when the first argument is zero. It was undefined before.
The details are in the <a href="/pkg/math/cmplx/#Pow">documentation for the function</a>.
</li>
<li> TODO: crypto/tls: add DialWithDialer (CL 68920045)</li>
<li> TODO: crypto/tls: report TLS version in ConnectionState (CL 68250043)</li>
<li> TODO: crypto/x509: support CSRs (CL 49830048)</li>
<li> TODO: fmt %F: 77580044</li>
<li> TODO: liblink: pull linker i/o into separate liblink C library (CL 35790044)</li>
<li>
The formatted print functions of the <code>fmt</code> package now define <code>%F</code>
as a synonym for <code>%f</code> when printing floating-point values.
</li>
<li> TODO: net/http: add Request.TLS (CL 52660047)</li>
<li> TODO: net/http: add Server.ErrorLog; log and test TLS handshake errors (CL 70250044)</li>
<li> TODO: net/http: add Server.SetKeepAlivesEnabled (CL 69670043)</li>
<li> TODO: net/http: add Transport.TLSHandshakeTimeout; set it by default (CL 68150045)</li>
<li> TODO: net/http: add optional Server.ConnState callback (CL 69260044)</li>
<li> TODO: net/http: use TCP Keep-Alives on DefaultTransport's connections (CL 68330046)</li>
<li> TODO: net/http: use TCP keep-alives for ListenAndServe and ListenAndServeTLS (CL 48300043)</li>
<li> TODO: net: add Dialer.KeepAlive option (CL 68380043)</li>
<li> TODO: net: enable fast socket creation using SOCK_CLOEXEC and Accept4 on FreeBSD 10 (69100043)</li>
<li> TODO: os/exec: fix Command with relative paths (CL 59580044)</li>
<li> TODO: regexp: add one-pass optimization from RE2 (CL 13345046)</li>
<li> TODO: runtime/debug: add SetPanicOnFault (CL 66590044)</li>
<li> TODO: runtime: output how long goroutines are blocked (CL 50420043)</li>
<li> TODO: runtime: better handling of defers, reduces goroutine memory footprint by 2K (CL 42750044)</li>
<li> TODO: runtime: faster GC: concurrent sweep, better parallelization, 8K pages (up to 50-70% pause reduction) (CL 46430043, 46860043, 58230043)</li>
<li> TODO: runtime/race: faster by ~40% (CL 55100044)</li>
<li> TODO: strconv.CanBackquote rejects U+007F CL 77300043</li>
<li>
The <a href="/pkg/os/exec/"><code>os/exec</code></a> package now implements
what the documentation has always said with regard to relative paths for the binary.
In particular, it only calls <a href="/pkg/os/exec/#LookPath"><code>LookPath</code></a>
when the binary's file name contains no path separators.
</li>
<li>
The <a href="/pkg/strconv/#CanBackquote"><code>CanBackquote</code></a>
function in the <a href="/pkg/strconv/"><code>strconv</code></a> package
now considers the <code>DEL</code> character, <code>U+007F</code>, to be
non-printing.
</li>
<li> TODO: syscall: add Accept4 for freebsd (CL 68880043)</li>
<li> TODO: syscall: add NewCallbackCDecl to use for windows callbacks (CL 36180044)</li>
<li> TODO: syscall: add support for FreeBSD 10 (CL 56770044, 56980043)</li>
<li> TODO: testing: add b.RunParallel function (CL 57270043)</li>
<li> TODO: testing: diagnose buggy tests that panic(nil) (CL 55780043)</li>
<li> TODO: unicode: upgrade from Unicode 6.2.0 to 6.3.0 (CL 65400044)</li>
<li>
The <a href="/pkg/testing/"><code>testing</code></a> package now
diagnoses tests that call <code>panic(nil)</code>, which is almost always erroneous.
</li>
<li>
The <a href="/pkg/unicode/"><code>unicode</code></a> package and associated
support throughout the system has been upgraded from
Unicode 6.2.0 to <a href="http://www.unicode.org/versions/Unicode6.3.0/">Unicode 6.3.0</a>.
</li>
</ul>