https://bugs.adobe.com/jira/browse/FP-1802

please vote and spread the word so this gets fixed!

=
150:559 : 219:459

vs.

+=
147:592 : 834:459

(code in the loops is the same as the last example, just in one test we’re assigning to sum, in the other test we’re adding to it)

these are the performance numbers we expect from a strongly typed Vector vs. a normal Array as the compiler should be able to negate RTI (run-time type identification)

Note: compiling against flex 3.3 and flex 4(most recent nightly) yielded no performance differences.

import __AS3__.vec.Vector;

with that I found that my vector was VERY slow if I didn’t use a POD

tick counts for processing an array of 10mill items
first number set is vector, second is array
first number is a normal forloop, second is for each

for this test I casted the results for just the array forloop and left the vector naked:

sum += vec_buff[i].foo;

I made a small custom class that inherited from a small base class with a single public variable (foo)

2552:1143 : 1512:1175

as you can see a typed foreach loop is the same speed as an array, but a uncasted forloop is VERY slow.

I did not experience this issue when I filled the arrays with PODs (uint for example)

I just recently _removed_ that import, and am now getting numbers about the same speed as a casted array (slight, VERY slightly better) in the forloops

Also note: easy way to detect if this is a problem, try to assign the vector element to an incorrect type, the imported version will NOT throw an error with strict type enabled, whereas the native version will (sum = vec_buff[i]; should throw an error but does not with imported version)

I’m using Flex 3.3 lastest stable build

Depending on what they are doing behind the scenes to create the the typed array, it could be that the only real performance benefit will occur when you use primitives.

Derek

Array -> non-typed, has to be checked at runtime
Vector -> typed, faster, no check for type

I am happy enough, that i have a field which is typed now, but there was this little abstract about performance and Vector in the docs

Glad it piqued your interest, though.

cu, jd/adobe

http://opensource.adobe.com/wiki/display/flexsdk/Targeting+Flash+Player+10+Beta+with+Flex+SDK+3.0.x

The SWF was opened in Browser (FF 3). Are there any compiler-tags to produce release/environment swf for Flex?
I have used a nightly build of the SDK from this week and compile it with “mxlmc VectorSpeedFP10Test.as”