3 ms·

That's wonderful. Can you help me understand why every single button click on Reddit has an 800ms user visible latency gap? Reddit has always been this way, eve

by jart 2y ago

That's wonderful. Can you help me understand why every single button click on Reddit has an 800ms user visible latency gap? Reddit has always been this way, ever since its very beginning. Its latency has always been so slow compared to Hacker News. Why can't Reddit go snappy like HN? Is Python just really really slow compared to LISP? Why didn't your bloom filter improve user visible latency?

jedberg 2y ago
I can't tell if you're trolling or serious. If you're serious, I think the problem may be on your end, because I don't see that latency, and when I worked there, we didn't see that latency either. My average latency on reddit is about 150ms, most of that network transit time. Some calls are slow, yes, but on average site wide when I worked there is was about 300ms (yes we measured it). > Is Python just really really slow compared to LISP? Now I'm almost certain you're trolling. Reddit was originally written in LISP. It was rewritten to Python for a massive speedup. Then we rewrote parts of it in C for another speedup. And now I'm pretty sure they have Rust and Golang too. Also, I'm pretty sure HN isn't in Arc anymore.
- jart 2y ago
  I am serious. If you're not logged in then reddit pages will take 150ms to respond if you exclude the snooserv ?rdt=xxxx redirect (which makes it take 200ms total). master jart@luna:~/cosmo$ time curl --tcp-fastopen -L 'https://www.reddit.com/r/torties/comments/1hldi83/i_adopted_two_girls/' 2>/dev/null | head -c1 >/dev/null real 0m0.203s user 0m0.016s sys 0m0.006s But if you're logged in as "jart" and use that chrome inspect feature to "copy as curl command" and run it on the shell, then the above URL takes 800ms to respond. Pretty much every page on Reddit takes 800ms+ to send back the first byte of content. Yes I use old reddit mode. I imagine the same problem afflicts all your long time loyal fans who uses Reddit while logged in. FWIW my ping to reddit.com is 4.5ms.
  - jedberg 2y ago
    Something is broken in your profile then. I also use old reddit and most pages load within 150ms for me.
    - jart 2y ago
      Any idea how I get unbroken?
      - jedberg 2y ago
        You could contact them but honestly that probably wouldn't work very well. Things that might help: switch your settings from old reddit to new reddit, use new reddit to load a few pages, and then switch back. Also try using "newest" reddit at https://sh.reddit.com https://sh.reddit.com.
        jart 2y ago
        Hey that brought it down to about 650ms. Thank you! That's a noticeable improvement.

by jart 2y ago

jedberg 2y ago

I can't tell if you're trolling or serious. If you're serious, I think the problem may be on your end, because I don't see that latency, and when I worked there, we didn't see that latency either. My average latency on reddit is about 150ms, most of that network transit time. Some calls are slow, yes, but on average site wide when I worked there is was about 300ms (yes we measured it). > Is Python just really really slow compared to LISP? Now I'm almost certain you're trolling. Reddit was originally written in LISP. It was rewritten to Python for a massive speedup. Then we rewrote parts of it in C for another speedup. And now I'm pretty sure they have Rust and Golang too. Also, I'm pretty sure HN isn't in Arc anymore.

jart 2y ago
I am serious. If you're not logged in then reddit pages will take 150ms to respond if you exclude the snooserv ?rdt=xxxx redirect (which makes it take 200ms total). master jart@luna:~/cosmo$ time curl --tcp-fastopen -L 'https://www.reddit.com/r/torties/comments/1hldi83/i_adopted_two_girls/' 2>/dev/null | head -c1 >/dev/null real 0m0.203s user 0m0.016s sys 0m0.006s But if you're logged in as "jart" and use that chrome inspect feature to "copy as curl command" and run it on the shell, then the above URL takes 800ms to respond. Pretty much every page on Reddit takes 800ms+ to send back the first byte of content. Yes I use old reddit mode. I imagine the same problem afflicts all your long time loyal fans who uses Reddit while logged in. FWIW my ping to reddit.com is 4.5ms.
- jedberg 2y ago
  Something is broken in your profile then. I also use old reddit and most pages load within 150ms for me.
  - jart 2y ago
    Any idea how I get unbroken?
    - jedberg 2y ago
      You could contact them but honestly that probably wouldn't work very well. Things that might help: switch your settings from old reddit to new reddit, use new reddit to load a few pages, and then switch back. Also try using "newest" reddit at https://sh.reddit.com https://sh.reddit.com.
      - jart 2y ago
        Hey that brought it down to about 650ms. Thank you! That's a noticeable improvement.