974235 - [B2G][Contacts] Scrolling long contacts list results in white spaces, some jankiness

Status: RESOLVED DUPLICATE of bug 942750

(Firefox OS Graveyard :: Gaia::Contacts, defect)

Description

[John Hammink]

Attachment: scrolling_jank.3gp

Gaia      df60e9b49207d64da5647ab15760c122adabfba4
Gecko     https://hg.mozilla.org/releases/mozilla-b2g28_v1_3/rev/b5afe0b10e93
BuildID   20140218004003
Version   28.0
ro.build.version.incremental=324
ro.build.date=Thu Dec 19 14:04:55 CST 2013

Description:
Scrolling a very long contact list results in jankiness and white space.   There are some memory allocation issues in the logfile (attached, excerpt below).

Repro Steps:
Scroll a list with > 700 contacts that takes more than 30 seconds to scroll.   

Actual:

There are some spots (about :21 into the video, for example) where scrolling is happening but screen goes - and stays  - white, until the buffer has a chance to load again.  It's impossible to tell where you are in the scrolling contacts when this happens.

logcat shows, in some places:
E/memalloc(  135): /dev/pmem: No more pmem available
W/memalloc(  135): Falling back to ashmem
E/memalloc(  135): /dev/pmem: No more pmem available
W/memalloc(  135): Falling back to ashmem

Expected:
Scrolling should always show text.


Logcat and video attached

Comment 1

[John Hammink]

Attachment: scrolling_jank.log

Comment 2

[John Hammink]

Nomming this.   IMO, it's more of a paper cut than an essential bug, but nonetheless a perception issue.

Comment 3

[Joe Cheng [:jcheng] (please needinfo)]

triage: base on the video, its not easy to reproduce and it recovers automatically. minus

potentially a APZC bug?

Comment 4

[Julien Wajsberg [:julienw] (PTO -> may 13)]

Basically it happens when you scroll very fast, looks like the "content" is not ready to be displayed, so I wonder if there is some fine tuning that could be done in APZC.

Comment 5

[Kartikaya Gupta (email:[e-mail])]

This is checkerboarding. Sounds like a dupe of bug 942750.