Bug 145526

Summary:

[Content Extensions] Reduce DFA memory usage.

Product:

WebKit

Reporter:

Alex Christensen <achristensen>

Component:

WebCore Misc.

Assignee:

Alex Christensen <achristensen>

Status:

RESOLVED FIXED

Severity:

Normal

Priority:

Version:

528+ (Nightly build)

Hardware:

Unspecified

OS:

Unspecified

Attachments:

Description	Flags
Patch	benjamin: review+

Description Alex Christensen 2015-06-01 14:32:47 PDT

std::pair<uint8_t, uint32_t> uses 8 bytes per transition, but we can reduce the memory usage of the DFA by about 3/8 by separating the characters from the destinations.

Comment 1 Alex Christensen 2015-06-01 14:34:23 PDT

Created attachment 254013 [details]
Patch

Comment 2 Benjamin Poulain 2015-06-01 15:24:11 PDT

Comment on attachment 254013 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=254013&action=review

> Source/WebCore/contentextensions/DFA.cpp:43
> +        + transitionCharacters.size() * sizeof(uint8_t)
> +        + transitionDestinations.size() * sizeof(uint8_t)

This should be capacity(), not size().

Comment 3 Alex Christensen 2015-06-01 15:29:34 PDT

Comment on attachment 254013 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=254013&action=review

>> Source/WebCore/contentextensions/DFA.cpp:43
>> +        + transitionDestinations.size() * sizeof(uint8_t)
> 
> This should be capacity(), not size().

And destinations are uint32_t.

Comment 4 Alex Christensen 2015-06-01 15:30:10 PDT

http://trac.webkit.org/changeset/185078