Bug 26064 - ListView, ImageCell and disabled source cache and same image url leads to degraded performance
Summary: ListView, ImageCell and disabled source cache and same image url leads to deg...
Alias: None
Product: Forms
Classification: Xamarin
Component: Forms ()
Version: 1.3.1
Hardware: Macintosh Mac OS
: Normal normal
Target Milestone: 1.3.3
Assignee: Bugzilla
Depends on:
Reported: 2015-01-15 09:11 UTC by Ota Mares
Modified: 2015-02-04 09:19 UTC (History)
7 users (show)

Is this bug a regression?: ---
Last known good build:

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Description Ota Mares 2015-01-15 09:11:19 UTC
Probably a very uncommon scenario: Using a ListView, with ImageCell, an ImageSource that has caching disabled AND loading the same image uri multiple times leads to very degraded loading performance.
It seems that the images get loaded one by one instead of parallel. Besides that, as soon as the image is scrolled out of view it gets never reloaded.

Example solution can be found at https://github.com/rebuy-de/xamarin-listview/tree/disabled_caching
Comment 1 Ota Mares 2015-01-15 09:12:00 UTC
Build env:

Xamarin Studio
Version 5.7 (build 661)
Installation UUID: 09a0b9f2-789f-44e5-90c2-9cb09673d175
    Mono 3.12.0 ((detached/a813491)
    GTK+ 2.24.23 (Raleigh theme)

    Package version: 312000068

Apple Developer Tools
Xcode 6.1.1 (6611)
Build 6A2008a

Version: (Trial Edition)
Hash: dfb682f
Build date: 2015-01-08 13:39:32-0500

Version: (Trial Edition)
Android SDK: /Users/otamares/Library/Developer/Xamarin/android-sdk-macosx
    Supported Android versions:
        2.1   (API level 7)
        2.2   (API level 8)
        2.3   (API level 10)
        3.1   (API level 12)
        4.0.3 (API level 15)
        4.1   (API level 16)
        4.4   (API level 19)
        5.0   (API level 21)
Java SDK: /usr
java version "1.7.0_67"
Java(TM) SE Runtime Environment (build 1.7.0_67-b01)
Java HotSpot(TM) 64-Bit Server VM (build 24.65-b04, mixed mode)

Not Installed

Build Information
Release ID: 507000661
Git revision: b70bab61da996da29045ea8ee8aed1a6faedbe78
Build date: 2015-01-05 16:31:31-05
Xamarin addins: 82f6c71490562d6cd125a09287f441902fdac3d7

Operating System
Mac OS X 10.10.1
Darwin XXX 14.0.0 Darwin Kernel Version 14.0.0
    Fri Sep 19 00:26:44 PDT 2014
    root:xnu-2782.1.97~2/RELEASE_X86_64 x86_64
Comment 2 Atin 2015-01-15 10:02:46 UTC
I am also able to reproduce this issue,  images are loaded one by one instead of parallel and images gets never reloaded when user scrolled images on device.

Hence marking this as Confirmed.

Supplement info:
Application output: https://gist.github.com/Mohit-Kheterpal/ae5678b15627494861b1
ide logs: https://gist.github.com/Mohit-Kheterpal/33680640ec4556c09a23
adblogcat: https://gist.github.com/Mohit-Kheterpal/f19e6f3e06dccaabb2db

Environment info:
OSX 10.8.5
XS 5.7.1(build 5)
Comment 3 Jason Smith [MSFT] 2015-01-29 21:57:33 UTC
Should be fixed in 1.3.3-pre1
Comment 4 Udham Singh 2015-02-04 09:19:14 UTC
I have checked this issue with sample app given in bug description and observed that when we scroll the image list out of view images are getting loaded on by one. 

I have also checked this issue with Xamarin.Forms and observed that it's performance has been improve with Xamarin.Forms as compare to previous Xamarin.Forms version (Xamarin.Forms

As of now I am closing this issue, please feel free to reopen it if you still facing this issue.

Screencast : http://www.screencast.com/t/apUaA0iQBHl3

Environment Info : 


Mac OS X 10.9.5
Xamarin Studio 5.7.1 (build 17)
Mono 3.12.0 ((detached/a813491)
GTK+ 2.24.23 (Raleigh theme)
Xcode 6.1.1 (6611)
Xamarin.iOS (Business Edition)
Xamarin.Android (Business Edition)