Errors/Warnings/Bugs

[Pcmendes]

Hi all,

This is my very first post and I 'd like to report a small bug. The number of solved problems shown in my .png "badge" (https://projecteuler.net/profile/pcmendes.png) is usually 2-4 problems fewer than I actually solved. The number shown seems to vary a lot too.

Maybe there 's a cache out of whack somewhere. Actually I suspect my own browser caches are confused, but maybe this could be fixed on the server end somehow.

Thanks,
Paulo

PS. This is totally non-urgent as far as I'm concerned because I don't use the badge outside of PE.

[euler]

It is quite possibly a bug I am unaware of, but recently I posted this comment.

Your actual profile is updated real time, but each of those profile images require information from the DB. You could imagine the number of transactions required by the server when, say, someone views a thread on this forum which contains several profile images. For that reason each of the images are cached and if it is less than one hour old then it displays the cached image, otherwise it will regenerate the image.

If the numbers are not matching up after more than one hour then please let me know. However, at the moment your badge shows 49 problems which is exactly how many problems you have currently solved.

[Pcmendes]

Indeed the badge in my signature was showing the correct number when I sent my initial message. When I opened the link to the badge (i.e., just the pcmendes.png file in its own window), it was correct as well.

But, at the same time I wrote my earlier message, the badge in my profile page in projecteuler.net showed 47. The error persisted after I refreshed the page. All this was on an iPad.

Now, 4 hours later, I've switched to my desktop and the badge shows 45 (!) both on the forum and on the profile page.

Btw this occurs only on the badge; the other info about my progress is always correct.

[euler]

Sorry, but I'm at a compete loss!? Your badge is showing 49 problems solved to me.

Is anyone else experiencing this issue? Any ideas why?

[nicolas.patrois]

Maybe his Firefox’ cache.

[Pcmendes]

I'm using Chrome on a PC and Safari on an iPad. Right now Chrome's showing correctly, but the iPad's stuck at 47 and level 1 instead of 2 (I bagged 2 problems since my previous post).

This time refreshing the page on the iPad worked partially: the badge's showing correctly on my profile, but when I opened the badge in its own window it showed just 50.

I agree with Patrois that there should be a stale cache somewhere—probably on my end. Well, any input is appreciated.

[nicolas.patrois]

Here is what I see:

[euler]

Curious, nicolas.patrois. When I first viewed this thread it had Pcmendes's badge saying "Solved 49", but when I refreshed the page it changed to 52.

I've made some changes to the image generation script on the server. Could you let me know if it fixes the problem? (or causes some other undesirable effect!?)

[TripleM]

I've always found Apple browsers to be a bit finicky when it comes to caching.. it can sometimes take multiple refreshes to clear a cached asset, unlike a single hard refresh on a PC.

The new method (sending no-cache headers entirely, meaning every badge on a page needs re-downloading every time the page is visited, even if just flicking through pages of a forum thread) will definitely prevent that, but I'm not sure it's ideal - a huge majority of times each badge will now be downloaded unnecessarily, since they change rarely. A soft load of this forum page (where most of it is cached assets) has increased in bandwidth by about 40%.

If you're storing the last time a problem was solved, then the ideal solution would be using the Last-Modified and If-Modified-Since header/request method, so the image is only redownloaded when necessary (or is that what you were doing already?)

[euler]

Thanks for the feedback, TripleM. You make a very good point and server load is certainly a concern. I've removed the multiple "no-cache" settings and added Last-Modified to the header. Let us see if that fixes the problem.

[user202729]

One small error of the new forum:
The links in the pink box ("Don't post any spoilers" and "Comments, questions and clarifications about PE problems.") are wrong. It link to the old forum.

[hk]

Thanks. Fixed (I hope).

[Georg]

When there are new (unread) posts in an old thread I can jump to the first unread post using a link ending with "...&view=unread#unread". When there are no unread posts this link will go to the first (oldest) post on that page. It should go to the last (newest) post instead.

[euler]

Where are you talking about? On this forum or on the main website?

[Georg]

This forum.

[euler]

I can jump to the first unread post using a link ending with "...&view=unread#unread"

It took me a long time to find where you were talking about as you didn't really give me much to work with, and as it turns out it was certainly new to me. For those who are curious, or wish to laugh at the fact that I didn't even know about this, he is referring to the icons in each forum area next to each topic that are red (to indicate unread posts) as opposed to blue (indicating no unread posts).

After all that, I am sorry to say that this forum software (phpBB) is not written by me, so I have no control over bugs here. As I continue to ensure that we are running the latest versions, and assuming you feel strongly about it, you could report it to the phpBB developers: https://www.phpbb.com/community/viewforum.php?f=466

[asgerix]

The Project Euler web site seems to be down.
The front page works, but most of the sub pages return an http error code 500.

/asgerix

[hk]

Thanks asgerix.
Only the about page and the newpage seem to be working.

For the time being: people can use http://static.projecteuler.net/
This site contains the problems up to 522 with the possibility of answer checking.

Edit:
site is working again.
static pages have been updated to #547

[Valentyn_Shtronda]

Typo in problem 547: choosen -> chosen (twice).

[mpiotte]

Typo in problem 547: choosen -> chosen (twice).

Fixed. Thanks.