This is awesome! Great job!
Marissa (Reese) Morris | Cell Phone 303-506-3282 |
<mailto:re...@mozilla.com> re...@mozilla.com | Slack: #Marissa (Reese)
From: firefox-dev On Behalf Of Eric Rahm
Sent: Thursday, August 16, 2018 1:41 PM
To: firefox-dev ; dev-platform
Subject: Fission MemShrink Newsletter #2
Hi Folks!
The Fission MemShrink project has been chugging along quite nicely and a ton of
progress has been made over the past month. There's been a large focus on
reducing the JS memory usage and we've managed to drop the base content JS
measure
<https://treeherder.mozilla.org/perf.html#/graphs?timerange=2592000=autoland,1684872,1,4>
by ~1.1MB (17%) [1]:
<https://screenshotscdn.firefoxusercontent.com/images/c5046573-91bd-4ca1-98db-6290777e70c4.png>
Additionally we've started looking at the overhead of our many threads
<https://bugzilla.mozilla.org/show_bug.cgi?id=1476432> [2], drafted up some
ideas on reducing relocation overhead by adopting a fork server
<https://bugzilla.mozilla.org/show_bug.cgi?id=1470591> on linux/mac [3], and
we're looking at reducing the overhead of per process font related data
<https://bugzilla.mozilla.org/show_bug.cgi?id=648417> [4].
Below is a sampling of the bugs that have improved memory usage over the past
month, apologies if I left any off! Please feel free to point out other
improvements. All numbers are per content process.
JS improvements
* In a great example of every little bit counts, Kris Maglione reduced
memory usage by 405KB in various bugs that made us lazily load JS content (
<https://bugzilla.mozilla.org/show_bug.cgi?id=1472491> Bug 1472491,
<https://bugzilla.mozilla.org/show_bug.cgi?id=1473631> Bug 1473631,
<https://bugzilla.mozilla.org/show_bug.cgi?id=1474139> Bug 1474139,
<https://bugzilla.mozilla.org/show_bug.cgi?id=1474155> Bug 1474155,
<https://bugzilla.mozilla.org/show_bug.cgi?id=1479241> Bug 1479241,
<https://bugzilla.mozilla.org/show_bug.cgi?id=1479245> Bug 1479245,
<https://bugzilla.mozilla.org/show_bug.cgi?id=1479309> Bug 1479309,
<https://bugzilla.mozilla.org/show_bug.cgi?id=1479310> Bug 1479310,
<https://bugzilla.mozilla.org/show_bug.cgi?id=1479312> Bug 1479312,
<https://bugzilla.mozilla.org/show_bug.cgi?id=1479313> Bug 1479313,
<https://bugzilla.mozilla.org/show_bug.cgi?id=1479318> Bug 1479318,
<https://bugzilla.mozilla.org/show_bug.cgi?id=1480319> Bug 1480319,
<https://bugzilla.mozilla.org/show_bug.cgi?id=1480327> Bug 1480327,
<https://bugzilla.mozilla.org/show_bug.cgi?id=1483363> Bug 1483363)
* Kris also reduced memory usage by 494KB by getting rid of
MessageManager globals (Bug 1480244
<https://bugzilla.mozilla.org/show_bug.cgi?id=1480244> )
* Felipe Gomes reduced memory usage by 95KB by lazily loading JS content
(Bug 1369466 <https://bugzilla.mozilla.org/show_bug.cgi?id=1369466> , Bug
1470324 <https://bugzilla.mozilla.org/show_bug.cgi?id=1470324> )
* Mike Kaply reduced memory usage by 65KB by converting an add-on to in
tree telemetry (Bug 1475571
<https://bugzilla.mozilla.org/show_bug.cgi?id=1475571> )
* Dão Gottwald reduced memory uasge by 57KB by lazily generating
thumbnails for the Ctrl+Tab panel (Bug 1481321
<https://bugzilla.mozilla.org/show_bug.cgi?id=1481321> )
* Nick Nethercote reduced memory usage by 44KB by making
mozilla::HashMaps lazily allocate their storage (Bug 1481998
<https://bugzilla.mozilla.org/show_bug.cgi?id=1481998> )
* Benjamin Bouvier reduced memory usage by 25KB by removing SIMD.js (Bug
1416723 <https://bugzilla.mozilla.org/show_bug.cgi?id=1416723> )
Threading Overhead
* Kris added measurements for thread stacks across platforms (Bug 1475899
<https://bugzilla.mozilla.org/show_bug.cgi?id=1475899> , Bug 1476405
<https://bugzilla.mozilla.org/show_bug.cgi?id=1476405> , Bug 1477512)
<https://bugzilla.mozilla.org/show_bug.cgi?id=1477512>
* Kris reduced memory usage on Linux by ~3MB (that's megabytes!) by
changing our default stack size (Bug 1476828
<https://bugzilla.mozilla.org/show_bug.cgi?id=1476828> )
* Eric Rahm (this author) reduced memory usage by 50KB by reducing the
amount of networking threads (Bug 1448034
<https://bugzilla.mozilla.org/show_bug.cgi?id=1448034> )
* Xidorn Quan committed an upstream Rust patch (rust-lang/rust#52847
<https://github.com/rust-lang/rust/issues/52847> ) to fix how stack sizes are
set on windows after Kris' initial investigation (Bug 1479250
<https://bugzilla.mozilla.org/show_bug.cgi?id=1479250> )
Font Overhead
* The winner of biggest improvement with the smallest change goes to Lee
Salzman who reduced memory usage on OSX by 10MB by reducing the skia glyph
cache (Bug 1258781 <https://bugzilla.mozilla.or
