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How to Make Common Lisp go Faster Than C
- deleted 18y ago[deleted]
- smanek 18y agoOh, and sorry. I actually submitted a link to the PDF directly, but YCNews scribd it and now it's unreadable. Here is the original: http://www.lrde.epita.fr/~didier/research/verna.06.imecs.pdf http://www.lrde.epita.fr/~didier/research/verna.06.imecs.pdf
- fff123 18y agoThis is ridiculous. They should change the name back to YC News since they've decided to shill for their own investments.
- deleted 18y ago[deleted]
- jcromartie 18y agoThis scribd thing is getting ridiculous. Why not make it an opt-out arrangement for submitters?
- dpapathanasiou 18y agoAnd while they're at it, they could also check for duplicate submissions: http://news.ycombinator.com/item?id=172432 http://news.ycombinator.com/item?id=172432
- jcl 18y agoThey do check. The sequence of events here seems to be: - Person submits PDF article. - HN rewrites article to scribd link. - People complain about scribd link. - Admin manually corrects link to point directly to PDF. - A month later, another person submits same PDF article. - HN rewrites article to scribd link, but because the original article was manually corrected, the scribd link doesn't match the original article, so it doesn't register as a dupe.
- dpapathanasiou 18y agoBut wouldn't either the original pdf link or the resulting scribd link show up as a duplicate in HN's dupe checker, since both were in the submitted list at one time or another?
- jcl 18y agoLook at the link in http://news.ycombinator.com/item?id=172432 http://news.ycombinator.com/item?id=172432 ... It's been changed from the scribd link to the original pdf file. I'm guessing they only check for dupes against a list of the current article links, and that they don't maintain a separate list of submitted links (which, except for cases like this one, would be the same list).
- dpapathanasiou 18y agoIt's been changed from the scribd link to the original pdf file. Ah, I didn't see that (I thought once it's been trans-scribd, it stays that way). But that raises another question: if http://news.ycombinator.com/item?id=172432 http://news.ycombinator.com/item?id=172432 points to the original pdf (i.e., http://www.lrde.epita.fr/~didier/research/verna.06.imecs.pdf http://www.lrde.epita.fr/~didier/research/verna.06.imecs.pdf) and the guy who submitted this also posted the same original pdf link, why wasn't it detected as a dupe right then?
- jcl 18y agoThe scribdfication must take place before duplicate-checking.
- orib 18y agoI sense that there's a simple solution to this. Perhaps we could drop the automatic scribdifynig of PDF links?
- dpapathanasiou 18y agoI'm not sure why HN auto-posts to scridb. If they're trying to send more traffic to that site, then we're S.O.L. OTOH, if they're just trying to increase the number of documents in scribd's repository, then a parallel submission process would be the solution. I.e., keep HN posts pointing to the original pdf, but also auto-submit to scribe, behind the scenes in a separate thread.
- ExplodingBob 18y agoThe Scribd file was degraded in quality to absolute illegibility, I had to grab the original link out of the URL just so I could read it. Opt-out? It's annoying. They should just stop doing it for everyone perhaps, or just use it as a backup in case the site is knocked off line by the influx of social news traffic.
- Hexstream 18y ago"While Lisp is mainly known for its basement on list processing, the Common Lisp standard features very efficient data types such as specialized arrays, structs or hash tables, making lists almost completely obsolete." Uh?!?
- spydez 18y agoNo one uses lists in a LISt Processing language. :P
- Zak 18y agoMany of the interesting macros I've seen use list operations heavily to slice and dice their arguments and body code. Most experienced Lispers use macros quite a bit.
- jrockway 18y agoAuthors of computer science papers aren't exactly known for their command of the finer points of the English language. basement?
- sah 18y agoIn languages that can mutate data structures using side-effects, linked lists are rarely the best choice of data structure. Note, for example, that Python and Ruby have built-in array-based lists, but no linked lists. Similar structures are the default for lists in C++, Java, and C#. That said, I'm pretty sure people use linked lists a lot in Common Lisp.
- deleted 18y ago[deleted]
- cheponis 18y agoWe can hack around the scribd censorship. Everybody who aubmits a .pdf knows it will be converted into the useless scribd format. So, the original submitter needs to immediately post a comment that is the original .pdf link. If HN scribd damage occurs on that link, then we will find other ways to route around that damage, for example, by using tinyurl. Down with scribd!!!
- jmatt 18y agohttp://www.lrde.epita.fr/~didier/research/verna.06.imecs.pdf http://www.lrde.epita.fr/~didier/research/verna.06.imecs.pdf There is an easy work around for this. Submit the pdf link. Then comment with the pdf link. That adds one level of indirection, until pg gets around to fixing it. This is hacker news, So I'm assuming people can use their browser and copy and paste. 1) copy link location. 2) paste link location in address bar. 2) remove scribd.com crap, leaving the original pdf link. 3) load original pdf link.
- gibsonf1 18y agoMy co-founder tried out some of the techniques in the paper on our system: "I was skeptical, probably because I've never done much performance tuning like this. But I changed (triples) to create a 2-d array of fixnums instead of the default list of lists from the select. I added the declarations. It's about 100x faster. 100!" Very nice :)
- mark-t 18y agoHow did this comment end up in the rss feed? Interestingly, the "comments" link for it points to http://news.ycombinator.com/item?id=196342 http://news.ycombinator.com/item?id=196342 -- the original post without any comments shown!
- ambition 18y agoIt was submitted as a standalone post. There are no comments on the new submission.
- xirium 18y agoWhen I mentioned that it may be possible for a web startup in beta to improve the speed of their code by a factor of 1024 over no particular timescale, I was downmodded by five points ( http://news.ycombinator.com/item?id=187692 http://news.ycombinator.com/item?id=187692 ). I can only advise that you shouldn't quit while you're ahead. Now that you've eliminated the most obvious performance bottlenecks, you may find that less obvious bottlenecks have emerged. Removing these could give you an additional factor of 10 improvement.
- scott_s 18y agoProbably not. Remember Amdah's Law: http://en.wikipedia.org/wiki/Ahmdal%27s_Law http://en.wikipedia.org/wiki/Ahmdal%27s_Law
- xirium 18y agoI'm aware of Amdahl's law. I also know of a case where adding an index to a production database gave a factor of 1000 improvement. If your design started as a proof-of-concept, you made a rash assumption, you had a tight deadline or you're just plain incompetent then there's almost no lower bound to initial system efficiency.