Thread: Quoting pictures?

That is an excellent idea.

It's tedious to scroll through repeated pictures, often with just a short sentence commenting at the end of them. Must chew up some disk space as well.

It is tedious to scroll down the same pictures over and over, however I don't believe that it makes a lot of difference on speed as once down loaded the pictures would be reused everytime they are quoted. Also as the pictures are not kept on the forum but on some other location and just pointed at they don't take up any more room than a URL.

I could be wrong as I am no expert

It makes a huge amount of difference if you are on dial up, like I am when down on the farm.

Personally even on the cable broadband I find it annoying if there is no reason for it. However there are occasions when to identify a single pic out of a group to make a reply understandable it is useful to copy the pic. BUT rarely!

Diana

I agree with all of the above, although I think the problem is not all that bad.

I recently went from dialup to satellite broadband, but have found it makes little difference to the speed of this site, although other sites are a lot faster now.

John

Originally Posted by JDNSW

........ I recently went from dialup to satellite broadband ........

John

More info please John. That's something I've been considering for a while, in relation to working in remote areas.

Cheers

I thought that if a picture was quoted it was downloaded only once and embedded in the threads, not a separate copy downloaded each time.

Am I wrong ?? (It did happen once before when I was younger )

I have to admit the number of repeated pics in a thread doesn't seem to make any difference to download speed - its either quick or takes ages to start, there doesn't seem to be a middle ground


Martyn

usually cached by your browser

but not always the case..

I should have replied here rather than Pedro's post...

Originally Posted by Ben

The question is, "Do images displayed in quoted text slow the forum down?"

The expert answer is yes, but not for the reasons, nor necessarily to the effect, your average user might think.

(breaking out of quote for readibility sake)

This is a little rushed, but hopefully explains the process:

Images are referenced by their URL in posts, so the quoted text would have a few extra bytes that have to be sent. Not a issue when serving a hundred people, can be an issue when serving millions. Image files on the other hand are quite a lot more bytes. Lots of people requesting large images/files at the same time would be an issue.

At the user's end, the first time the image file is downloaded it will be saved in the web browser's temporary cache (unless the cache settings have been changed), as are HTML, CSS and JavaScript files. Subsequent requests for these files will be served with the local cached copy.

Files will eventually get removed from the cache - maybe the expiry date is reached, the cache is cleared, the cache reaches its limit and the file is the oldest in the cache (first in, first out), or the browser finds out there's a newer version (modified date) on the server. In this case, the file is downloaded again.

So, a forum page might have three requests for a large image. The original post, and two replies quoting.

If the image is not in the browser's cache, it is requested from the server. If your ISP has a cache, it might send you their version, otherwise AURLO will serve the image file once.

The browser then displays the same image three times. If you've got a slow connection, you can often see the three instances of the image displaying line by line at the same time. Memory is a factor, as the GUI subsystem has to put everything together for rendering, so this could affect lower-end machines.

Our user clicks to page two, where the image is displayed in four more posts. Once again, the web brower checks if the image is in its cache, if not it requests it from the server. Again, an ISP level cache might serve a copy, otherwise AURLO serves the request.

Some people change their cache settings. My work is building websites, so all my web browsers are set to always request a server's files so I see exactly what the server will be serving.

I still only request the image once from AULRO, regardless of how many times it appears on the page. But, I have to download the image again for each subsequent page that requires that file.


In a nutshell, do quotes containing images affect forum speed?

Server-wise, most likely negligible. The real hit is serving large files. Compounded by lots of users requesting large files at the same time.

User-wise, depends on hard-drive space (often a factor in cache-size determination), memory (has to hold all the display data), CPU power. Also internet connection speed - if that 2mb image on page 1 isn't cached, you'll redownload it when it's quoted on page 2, 3...

This isn't only an issue for low-end machines, it can affect devices like PDAs, internet-enabled phones, etc.