Charles, Thanks for your suggestion. About global links_grabbed - I am sure there could be a better solution, but in my case it is not so significant. I have tried, just for testing, to store 200 thousands of large links in an array, and then I've outputed the used memory, and it's amount is very small. So I didn't focused on this :)* * * *
On Monday, July 2, 2012 4:44:24 PM UTC+3, Charles Care wrote: > > Hi, > > I had a play with your code and found a couple of things. It's > probably worth trying to avoid the global variable links_grabbed as > it's just getting larger and larger as you crawl. I know you need it > to avoid parsing the same site twice, but perhaps you could find a > more lightweight data structure? I'd probably be tempted to keep this > state in a Redis set (or something similar). > > Also, I'm not an expert on scraper, but I *seemed* to get a > performance improvement when I modified the code that pushed new urls > onto your links stack. > > I added a String() conversion: e.g. > > ... > links.push(String(link)); > ... > > which meant I wasn't keeping the jquery link around in a stack. Hope that > helps, > > Charles > > > > On 2 July 2012 14:08, ec.developer <[email protected]> wrote: > > Hi all, > > I've created a small app, which searches for Not Found [404] exceptions > on a > > specified website. I use the node-scraper module > > (https://github.com/mape/node-scraper/), which uses native node's > request > > module and jsdom for parsing the html). > > My app recursively searches for links on the each webpage, and then > calls > > the Scraping stuff for each found link. The problem is that after > scanning > > 100 pages (and collecting over 200 links to be scanned) the RSS memory > usage > > is >200MB (and it still increases on each iteration). So after scanning > over > > 300-400 pages, I got memory allocation error. > > The code is provided below. > > Any hints? > > > > var scraper = require('scraper'), > > util = require('util'); > > > > var checkDomain = process.argv[2].replace("https://";, > "").replace("http://";, > > ""), > > links = [process.argv[2]], > > links_grabbed = []; > > > > var link_check = links.pop(); > > links_grabbed.push(link_check); > > scraper(link_check, parseData); > > > > function parseData(err, jQuery, url) > > { > > var ramUsage = bytesToSize(process.memoryUsage().rss); > > process.stdout.write("\rLinks checked: " + > > (Object.keys(links_grabbed).length) + "/" + links.length + " ["+ > ramUsage > > +"] "); > > > > if( err ) { > > console.log("%s [%s], source - %s", err.uri, err.http_status, > > links_grabbed[err.uri].src); > > } > > else { > > jQuery('a').each(function() { > > var link = jQuery(this).attr("href").trim(); > > > > if( link.indexOf("/")==0 ) > > link = "http://"; + checkDomain + link; > > > > if( links.indexOf(link)==-1 && links_grabbed.indexOf(link)==-1 && ["#", > > ""].indexOf(link)==-1 && (link.indexOf("http://"; + checkDomain)==0 || > > link.indexOf("https://"+checkDomain)==0) ) > > links.push(link); > > }); > > } > > > > if( links.length>0 ) { > > var link_check = links.pop(); > > links_grabbed.push(link_check); > > scraper(link_check, parseData); > > } > > else { > > util.log("Scraping is done. Bye bye =)"); > > process.exit(0); > > } > > } > > > > -- > > Job Board: http://jobs.nodejs.org/ > > Posting guidelines: > > https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines > > You received this message because you are subscribed to the Google > > Groups "nodejs" group. > > To post to this group, send email to [email protected] > > To unsubscribe from this group, send email to > > [email protected] > > For more options, visit this group at > > http://groups.google.com/group/nodejs?hl=en?hl=en > -- Job Board: http://jobs.nodejs.org/ Posting guidelines: https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines You received this message because you are subscribed to the Google Groups "nodejs" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/nodejs?hl=en?hl=en
