<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> </head> <body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""> Hi Michael, <div class=""><br class=""> </div> <div class=""> <blockquote type="cite" class="">We typically have one in Hamburg at some stage in the year - which<br class=""> would be near you; the ESC minutes have details on all of those as they<br class=""> come up (posted to this list weekly). We also have a larger hackfest in<br class=""> Brussels before or after FOSDEM - which is an excellent conference to<br class=""> attend anyway =)</blockquote> <div class=""><br class=""> </div> Yes, that’s very close :) Thanks! I can see there is also a tentative LibreOffice Conference</div> <div class="">announced <a href="https://wiki.documentfoundation.org/Events/2019" class="">in the wiki</a>. Thanks for the FOSDEM recommendation!</div> <div class=""><br class=""> </div> <div class=""> <blockquote type="cite" class="">Only in very recent times (the last generation) has typical GPU<br class=""> hardware become capable of running multiple kernels simultaneously<br class=""> and/or pre-empting running kernels. This leads to amusing situations -<br class=""> whereby moving the mouse while a long running sheet calculates would<br class=""> simply not be able to render - until a Windows / TDR was triggered. We<br class=""> had to come up with heuristics to break down the CL workload into<br class=""> bite-sized chunks to avoid this. More modern hardware doesn't have this<br class=""> issue though.</blockquote> <div class=""><br class=""> </div> <div class="">Interesting stuff :)</div> <div class=""><br class=""> </div> <div class=""> <blockquote type="cite" class="">And yes, we use CL when we think it makes sense - based on weights and<br class=""> complexity of the relevant formulae. Otherwise we use the old<br class=""> interpreter (or now its threaded variant - again depending on complexity).</blockquote> <br class=""> </div> <div class="">I like the practical approach using weights and formula complexity. We currently use a full</div> <div class="">big-step cost semantics for the formula language to estimate cost in the static partitioning</div> <div class="">algorithm. Unfortunately, assigning costs also results in quite a slowdown in the partitioning algorithm.</div> <div class="">As one of my colleagues said though, you can think of the process as compiling the spread-</div> <div class="">sheet into a partition that can scheduled to run on a set of multicore processors.</div> <div class=""><br class=""> </div> <div class="">The threaded variant you refer to is the one from the slides right? As I understand, the interpreter</div> <div class="">is not fully parallel but runs cell arrays/formula groups in parallel.</div> <div class=""> <div style="color: rgb(0, 0, 0); letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""> <div style="color: rgb(0, 0, 0); letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""> <div style="color: rgb(0, 0, 0); letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""> <div style="color: rgb(0, 0, 0); letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""> <div style="color: rgb(0, 0, 0); letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""> <div style="color: rgb(0, 0, 0); letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""> <div style="color: rgb(0, 0, 0); letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""> <div style="color: rgb(0, 0, 0); font-variant-caps: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""> <br class="Apple-interchange-newline"> Mvh/Best regards,</div> <div style="color: rgb(0, 0, 0); font-variant-caps: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""> <font face="Consolas" class=""><br class="Apple-interchange-newline"> <b class="">Alexander Asp Bock</b>, PhD student</font></div> <div style="color: rgb(0, 0, 0); font-variant-caps: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""> <a href="https://computerscience.wikit.itu.dk/" class=""><font face="Consolas" class="">Computer Science Department</font></a></div> <div style="color: rgb(0, 0, 0); font-variant-caps: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""> <a href="http://en.itu.dk/" class=""><font face="Consolas" class="">IT University of Copenhagen</font></a></div> </div> </div> </div> </div> </div> </div> </div> </div> <div><br class=""> <blockquote type="cite" class=""> <div class="">On 18 Sep 2018, at 11.55, Michael Meeks <<a href="mailto:michael.meeks@collabora.com" class="">michael.meeks@collabora.com</a>> wrote:</div> <br class="Apple-interchange-newline"> <div class=""> <div class="">Hi Alexander,<br class=""> <br class=""> On 18/09/18 10:26, Alexander Bock wrote:<br class=""> <blockquote type="cite" class="">I would be delighted to join one of the hackfests if time allows. Is<br class=""> there a schedule available somewhere?<br class=""> </blockquote> <br class=""> <span class="Apple-tab-span" style="white-space:pre"></span>We typically have one in Hamburg at some stage in the year - which<br class=""> would be near you; the ESC minutes have details on all of those as they<br class=""> come up (posted to this list weekly). We also have a larger hackfest in<br class=""> Brussels before or after FOSDEM - which is an excellent conference to<br class=""> attend anyway =)<br class=""> <br class=""> <blockquote type="cite" class="">I know of EUSPRIG as well and their horror stories<br class=""> <<a href="http://eusprig.org/horror-stories.htm" class="">http://eusprig.org/horror-stories.htm</a>><br class=""> </blockquote> <br class=""> <span class="Apple-tab-span" style="white-space:pre"></span>Some good stories there =) Thanks for the list of conferences.<br class=""> <br class=""> <blockquote type="cite" class="">Do you run any of the generated OpenCL kernels in parallel or do you run<br class=""> a normal sequential recalculation and call the kernel code as necessary?<br class=""> I would suspect the latter given the information you have provided so far :)<br class=""> </blockquote> <br class=""> <span class="Apple-tab-span" style="white-space:pre"></span>Only in very recent times (the last generation) has typical GPU<br class=""> hardware become capable of running multiple kernels simultaneously<br class=""> and/or pre-empting running kernels. This leads to amusing situations -<br class=""> whereby moving the mouse while a long running sheet calculates would<br class=""> simply not be able to render - until a Windows / TDR was triggered. We<br class=""> had to come up with heuristics to break down the CL workload into<br class=""> bite-sized chunks to avoid this. More modern hardware doesn't have this<br class=""> issue though.<br class=""> <br class=""> <span class="Apple-tab-span" style="white-space:pre"></span>And yes, we use CL when we think it makes sense - based on weights and<br class=""> complexity of the relevant formulae. Otherwise we use the old<br class=""> interpreter (or now its threaded variant - again depending on complexity).<br class=""> <br class=""> <span class="Apple-tab-span" style="white-space:pre"></span>HTH,<br class=""> <br class=""> <span class="Apple-tab-span" style="white-space:pre"></span><span class="Apple-tab-span" style="white-space:pre"></span>Michael.<br class=""> <br class=""> -- <br class=""> <a href="mailto:michael.meeks@collabora.com" class="">michael.meeks@collabora.com</a> <><, GM Collabora Productivity<br class=""> Hangout: <a href="mailto:mejmeeks@gmail.com" class="">mejmeeks@gmail.com</a>, Skype: mmeeks<br class=""> (M) +44 7795 666 147 - timezone usually UK / Europe<br class=""> </div> </div> </blockquote> </div> <br class=""> </div> </body> </html>