December 2016 - Pharo-users

Re: [Pharo-users] Hash collision

by Andres Valloud

Oh, ok... then the failure code isn't doing what was intended :). On 12/13/16 15:16 , Martin McClure wrote: > On 12/13/2016 08:39 AM, Andres Valloud wrote: >> I would have expected the floats to be a byte object of size 8. Why is >> this conversion needed? Is somehow the primitive thinking the float has >> size 2? Or is the primitive hashing 32 bits at a time? The prim used >> to be a C version of the byte oriented 1644525 multiplicative hash, did >> this change? > > The float is not a byte object of size 8, it's a word object of size 2. > > When you feed it to #hashBytes:startingWith: the primitive fails. (I > didn't look at why -- maybe because it isn't a byte object?) > > The alternative Smalltalk code treats it like it was a byte object, even > though it's not. So it iterates through the two words, multiplying each > by 1664525, then keeping only the low-order 28 bits of the result. But > since each word is a full 32 bits, the high-order four bits of each > word, which include the sign bit, can never affect the hash. > > Regards, > > -Martin >

Dec. 13, 2016

Re: [Pharo-users] Hash collision

by Martin McClure

On 12/13/2016 08:39 AM, Andres Valloud wrote: > I would have expected the floats to be a byte object of size 8. Why is > this conversion needed? Is somehow the primitive thinking the float has > size 2? Or is the primitive hashing 32 bits at a time? The prim used > to be a C version of the byte oriented 1644525 multiplicative hash, did > this change? The float is not a byte object of size 8, it's a word object of size 2. When you feed it to #hashBytes:startingWith: the primitive fails. (I didn't look at why -- maybe because it isn't a byte object?) The alternative Smalltalk code treats it like it was a byte object, even though it's not. So it iterates through the two words, multiplying each by 1664525, then keeping only the low-order 28 bits of the result. But since each word is a full 32 bits, the high-order four bits of each word, which include the sign bit, can never affect the hash. Regards, -Martin

Dec. 13, 2016

Re: [Pharo-users] [Pharo-dev] The Iceberg TechTalk recording

by Dimitris Chloupis

you can add an annotation for the first 10 minutes that links directly to the time the techtalk actually starts you can also link to the precise time like this https://youtu.be/AuZAFfWS34w?t=598 you can get this link by pushing the playback cursor to the time you want to link and then right click and choose Copy URL at current time On Tue, Dec 13, 2016 at 11:57 PM Nicolas Passerini <npasserini(a)gmail.com> wrote: > Maybe we could try to edit the video? Is it possible? > > 2016-12-13 21:20 GMT+01:00 Esteban Lorenzano <estebanlm(a)gmail.com>: > > Ah, but you need to skip until minute 10 :P > > Esteban > > > On 13 Dec 2016, at 21:19, Esteban Lorenzano <estebanlm(a)gmail.com> wrote: > > > > Hi, > > > > for those who couldnât join us, this is the recording: > > > > https://www.youtube.com/watch?v=AuZAFfWS34w > > > > I think it was a great talk :) > > > > cheers, > > Esteban > > >

Dec. 13, 2016

Re: [Pharo-users] The Iceberg TechTalk recording

by Nicolas Passerini

Maybe we could try to edit the video? Is it possible? 2016-12-13 21:20 GMT+01:00 Esteban Lorenzano <estebanlm(a)gmail.com>: > Ah, but you need to skip until minute 10 :P > > Esteban > > > On 13 Dec 2016, at 21:19, Esteban Lorenzano <estebanlm(a)gmail.com> wrote: > > > > Hi, > > > > for those who couldnât join us, this is the recording: > > > > https://www.youtube.com/watch?v=AuZAFfWS34w > > > > I think it was a great talk :) > > > > cheers, > > Esteban > >

Dec. 13, 2016

Modeling a join table

by sergio ruiz

Hello, all. This question is not as much a question about smalltalk as one about modeling in smalltalk. I am currently writing an API using Teapot that will be serving up data about internet radio stations. I want to be able to let users tag the stations with arbitrary tags. Using a relational database, I would create an object like "Tagging" with foreign keys pointing to the "Stations" class and the "Tag" Class. It would have station_id and tag_id. If this was going to be even a tiny bit more complex, I would probably just make it a polymorphic association.Â My question is, how would I approach this in smalltalk? Would I just make methods on tag and station (and whatever else) that stored arrays of each other? Would I create an intermediary model like "Tagging" and have that do the heavy lifting? Ideas? Thanks!; ---- peace, sergio photographer, journalist, visionary Public Key:Â http://bit.ly/29z9fG0 #BitMessageÂ BM-NBaswViL21xqgg9STRJjaJaUoyiNe2dV http://www.Village-Buzz.com http://www.ThoseOptimizeGuys.com http://www.coffee-black.com http://www.painlessfrugality.com http://www.twitter.com/sergio_101 http://www.facebook.com/sergio101

Dec. 13, 2016

Re: [Pharo-users] The Iceberg TechTalk recording

by Esteban Lorenzano

Ah, but you need to skip until minute 10 :P Esteban > On 13 Dec 2016, at 21:19, Esteban Lorenzano <estebanlm(a)gmail.com> wrote: > > Hi, > > for those who couldnât join us, this is the recording: > > https://www.youtube.com/watch?v=AuZAFfWS34w > > I think it was a great talk :) > > cheers, > Esteban

Dec. 13, 2016

The Iceberg TechTalk recording

by Esteban Lorenzano

Hi, for those who couldnât join us, this is the recording: https://www.youtube.com/watch?v=AuZAFfWS34w I think it was a great talk :) cheers, Esteban

Dec. 13, 2016

Re: [Pharo-users] real world pharo web application set ups

by Sven Van Caekenberghe

> On 13 Dec 2016, at 20:07, Volkert <volkert(a)nivoba.de> wrote: > > > > On 12.12.2016 20:05, Sven Van Caekenberghe wrote: >> Yes, it is a bit too wide a subject ;-) >> >> Anyway, all the cases you find at http://pharo.org/success are successful real-world deployments, but I am sure they are all quite different. > i looked already, but there is a problem with the page. all screenshots/pictures have a wrong scaling ... Hmm, they look fine on Safari and Google Chrome, but they seem off in Firefox - weird. >>> On 12 Dec 2016, at 19:52, Norbert Hartl <norbert(a)hartl.name> wrote: >>> >>>> Am 12.12.2016 um 19:16 schrieb Volkert <volkert(a)nivoba.de>: >>>> >>>> After reading reading "Enterprise Pharo a Web perspective", i am curious to learn more about current real world pharo web application set ups. any case studies or blue prints around? i am interested in application domain, system architecture, infrastructure (HW/OS/DB), performance goals (concurrent users, transactions, ...), system sizing, scalability strategies, .... >>>> >>>> everything which could important to convince "me" to select pharo as a platform for a saas solution â¦ >>>> >>> What you really want to know? All the things you mentioned above are not pharo related at all! Can you at least roughly sketch in which area you would consider to use pharo? >>> >>> Norbert >> > >

Dec. 13, 2016

Re: [Pharo-users] real world pharo web application set ups

by jtuchel＠objektfabrik.de

Volkert, I surely cannot help you with concrete answers. We are not even using Pharo for our Seaside App. All I've learned is that all of these questions are extremely hard to answer. Will Pharo or any other Server side technology scale? Forget it, nobody will be able to tell you the truth. What I've learnt so far is that this whole thing is mostly a question of distributing services between servers (images and external processes). Make things small and devidable. Load the number crunching off of your web facing image and build clever UIs that give good feedback about the progress of lengthy operations. If I tell you that my current estimate is that a Smalltalk image with Seaside will not be able to handle more than 20 concurrent users, in many cases even less. What does that actually tell you? YMMV based on the work that is done in that image, and there are so many influencing factors. If of these 20 users only 1 currently asks for heavy computation, this can already mean the server is slow for the other 19. Our Application is very different from what you describe: Accounting is mostly CRUD operations, which means there are not many things you can delegate to external programs or even servers. Your scenario sounds very different. It sounds like you can do the data aggregation and refinement part in a separate (maybe REST based and stateless) server and mostly render nice "wait, we're working for you" dialogs and present nice results once they're done. This scales wonderfully and the front-end web server mostly does nothing other than send out self-reloading please-wait pages. Such a server (image) can probably even handle 50 or more concurrent users. Thus you end up with several layers on which you can scale easily and mostly independently. If your aggreations are slow, add a few images that do the aggregations. So if your question is whether you can handle 500 concurrent users in Smalltalk or Pharo with Seaside, the answer is definitely YES. If you want to know how many Images are needed, how many servers you'd have to order, you'll probably not get any useful answers. My feeling is that you can't know exactly because every app is so different. There probably are just not enough projects out there to collect relevant data... Joachim Am 13.12.16 um 20:06 schrieb Volkert: > > > On 12.12.2016 19:52, Norbert Hartl wrote: >>> Am 12.12.2016 um 19:16 schrieb Volkert <volkert(a)nivoba.de>: >>> >>> After reading reading "Enterprise Pharo a Web perspective", i am >>> curious to learn more about current real world pharo web application >>> set ups. any case studies or blue prints around? i am interested in >>> application domain, system architecture, infrastructure (HW/OS/DB), >>> performance goals (concurrent users, transactions, ...), system >>> sizing, scalability strategies, .... >>> >>> everything which could important to convince "me" to select pharo as >>> a platform for a saas solution â¦ >>> >> What you really want to know? All the things you mentioned above are >> not pharo related at all! Can you at least roughly sketch in which >> area you would consider to use pharo? >> >> Norbert >> >> > I like to know more about current real world pharo web application set > up ... not more, not less. > > Think of a environmental information management system > 50000 User / 500 Concurrent > Data Aggregation > Data Refinement / Processing > Data Visualization > 15-20 Dataprovider > Web UI > > > > >

Dec. 13, 2016

Re: [Pharo-users] real world pharo web application set ups

by Sven Van Caekenberghe

> On 13 Dec 2016, at 19:48, Joe Shirk <j.b.shirk(a)gmail.com> wrote: > > Here is one I am really impressed with; I can't say just how much of it is Pharo: > > https://medium.com/concerning-pharo/pharo-beta-nine-59ee972d321a Well, not all of it is Pharo, far from it, but currently we have about 20 Pharo images running in production, doing various jobs ranging from web apps to various back end application server tasks under real world load. Sven > On Tue, Dec 13, 2016 at 12:00 PM, <pharo-users-request(a)lists.pharo.org> wrote: > ------------------ > > Message: 1 > Date: Mon, 12 Dec 2016 19:16:26 +0100 > From: Volkert <volkert(a)nivoba.de> > To: Any question about pharo is welcome <pharo-users(a)lists.pharo.org> > Subject: [Pharo-users] real world pharo web application set ups > Message-ID: <7b7e6144-724f-1eb7-8033-8cfe87a34ef6(a)nivoba.de> > Content-Type: text/plain; charset=utf-8; format=flowed > > After reading reading "Enterprise Pharo a Web perspective", i am curious > to learn more about current real world pharo web application set ups. > any case studies or blue prints around? i am interested in application > domain, system architecture, infrastructure (HW/OS/DB), performance > goals (concurrent users, transactions, ...), system sizing, scalability > strategies, .... > > everything which could important to convince "me" to select pharo as a > platform for a saas solution ... > > Thanks, > Volkert > > > >

Dec. 13, 2016