https://issues.qgis.org/https://issues.qgis.org/favicon.ico2011-12-04T11:51:10ZQGIS Issue TrackingQGIS Application - Feature request #4594: identify feature on ecw extremely longhttps://issues.qgis.org/issues/4594?journal_id=266992011-12-04T11:51:10ZGiovanni Manghigiovanni.manghi@gmail.com
<ul><li><strong>Status</strong> changed from <i>Open</i> to <i>Feedback</i></li></ul><p>With not that big ecws (~100mb) the identify operation is normal fast. Can you test with smaller images and/or with different formats?</p> QGIS Application - Feature request #4594: identify feature on ecw extremely longhttps://issues.qgis.org/issues/4594?journal_id=267042011-12-05T02:04:21ZRegis Haubourgregis.haubourg@oslandia.com
<ul></ul><p>Hi Ghiovanni, <br />here are result tests:</p>
<p>QGIS 1.7.2, on the fly "off", Xeon Windows xp 32 bits. ecw on NAS servers via LAN 100Mbit/s:</p>
<p>- scan 1 / Size: 139Mo / pixels : 12150 * 11000 (sdk ecw 4.1) / identify delay: 1s / RAM consumption : opening ecw + 50Mo, each identify action + ~ 15 Mo. Memory not released after identify</p>
<p>- scan 2 / Size: 525Mo/ pixels : 30000*30000 (sdk ecw 4.1) / identify delay: 4s / RAM consumption : opening ecw + 10Mo, each identify action + ~ 15 Mo. Memory not released after identify</p>
<p>- scan 3 / Size: 870Mo/ pixels : 60000*60000 (sdk ecw 4.1) / identify delay: 6s / RAM consumption : opening ecw + 30Mo, each identify action + ~ 15 Mo. Memory not released after identify</p>
<p>- scan 4 / Size: 1,05Go/ pixels : 220 000* 220 000 (sdk ecw 4.1) / identify delay: 20s / RAM consumption : opening ecw + 30Mo, identify action rises once RAM to 663 Mo! / Memory not released after identify</p>
<p>- aerial views / Size: 74 Go/ pixels : 1 080 000* 1 090 000 (sdk ecw 4.1) / identify delay: 50s / RAM consumption : opening ecw + 30Mo, identify action rises once RAM to 663 Mo! / Memory not released after identify. Many crashes if on-the_fly reprojection is "On" (true also on 1.7.1).</p>
<p>I tested 1.7.1 on a windows server 2003, with gigabit access to datas, (vmware environnement). only identify delay is shortened to 30 s instead of 50s. Crashes sometimes, 660 Mo of RAM consumption.</p>
<p>I guess gdal or Qgis uncompress datas and also have a memory leak. I have not noticed any improvement identifying on a hih or low scale (more pixels inside cursor tolerance?)</p>
<p>Régis</p> QGIS Application - Feature request #4594: identify feature on ecw extremely longhttps://issues.qgis.org/issues/4594?journal_id=267052011-12-05T02:31:33ZNathan Woodrow
<ul></ul><p>Just a note: The large memory usage with ecws is due to the caching the gdal driver does. We could turn this off as I don't find it improves performance a lot.</p> QGIS Application - Feature request #4594: identify feature on ecw extremely longhttps://issues.qgis.org/issues/4594?journal_id=268842011-12-14T05:22:48ZRegis Haubourgregis.haubourg@oslandia.com
<ul></ul><p>Thanks Nathan, I didn't find in source code where to toggle gdal cache off. Any idea? I also wanted to test the identify query directly in gdal command line. What is the query send by qgis to gdal? <br />Régis</p> QGIS Application - Feature request #4594: identify feature on ecw extremely longhttps://issues.qgis.org/issues/4594?journal_id=302522012-04-15T08:06:51ZGiovanni Manghigiovanni.manghi@gmail.com
<ul><li><strong>Target version</strong> changed from <i>Version 1.8.0</i> to <i>Version 2.0.0</i></li></ul> QGIS Application - Feature request #4594: identify feature on ecw extremely longhttps://issues.qgis.org/issues/4594?journal_id=340582012-08-22T09:23:10ZRadim Blazekradim.blazek@gmail.com
<ul></ul><p>The problem was that identify requested single pixel by GDALRasterIO() and GDAL ECW driver reads and caches whole line if requested block height is 1.</p>
<p>It should be fixed in master <a class="changeset" href="https://issues.qgis.org/projects/qgis/repository/revisions/a795a5d334d8954a5a78b81dbb777c86b627beb9" title="gdal identify with 2x2 block, hopefully fix for #4594 (slow identify with ecw">a795a5d334</a>.</p>
<p>Please test and close if it is resolved.</p> QGIS Application - Feature request #4594: identify feature on ecw extremely longhttps://issues.qgis.org/issues/4594?journal_id=340742012-08-22T23:43:08ZRegis Haubourgregis.haubourg@oslandia.com
<ul></ul><p>Problem is solved for me on <a class="changeset" href="https://issues.qgis.org/projects/qgis/repository/revisions/a795a5d334d8954a5a78b81dbb777c86b627beb9" title="gdal identify with 2x2 block, hopefully fix for #4594 (slow identify with ecw">a795a5d</a>. Thanks a lot guys. Can you close the bug? I don't have permissions apparently.</p> QGIS Application - Feature request #4594: identify feature on ecw extremely longhttps://issues.qgis.org/issues/4594?journal_id=340752012-08-22T23:43:57ZGiovanni Manghigiovanni.manghi@gmail.com
<ul><li><strong>Resolution</strong> set to <i>fixed</i></li><li><strong>Status</strong> changed from <i>Feedback</i> to <i>Closed</i></li></ul>