I am back from Mallorca.  I will try to post more info on X-Plane developer conferences soon, but for now I will only say: it was great to meet a bunch of developers and friends in person (indeed, one of the things I like most about flight simulation is that it brings people together, often from across continents) and any picture you see posted of me with copious quantities of beer or other alcohol are photoshopped.

We’ll be cutting an RC2 of X-Plane 10.04 pretty soon with a few minor changes – it should be ready in a day or two.

I am also looking at better memory error reporting for 10.05.  The crash reports now show memory usage at the time of crash and it’s clear that almost all of the crash reports we now get are memory exhaustion.  (Well, address space exhaustion, technically.)

I spent part of today looking at whether I could detect this case and put up a clean error message.  It turns out it’s very hard.  X-Plane uses multiple cores to load scenery, and as a result, we can run out of memory simultaneously on several cores. On my 8 core machine, it’s like having 8 race cars heading toward a brick wall at 200 mph and you only have one airbag.  Often a second thread will run out of memory and explode while we’re coping with the first one.

Clearly the long term solution is 64-bit, something that we are working on.  But I am hoping that for X-Plane 10.05 we can at least recover enough to put up a useful error message (e.g. “you ran out of memory”).  This will help users easily differentiate when they have to turn down settings vs. when they have found a real bug.

And speaking of using up memory…Andras has posted HD meshes, and they look awesome!

Finally, one last note on ATI Windows performance – I know everyone is itchy for an update, but here’s the thing: we have NDAs with AMD, NVidia, Apple, and Intel.  Therefore when we get information from them, I can’t post it here.  So unfortunately whether a bug is not being looked at, being looked at, understood, being fixed, or already fixed and just waiting to make it into some kind of release, I have to say the same thing: very little.  I know that that’s frustrating, but I think we’re better off having close relationships with these companies and being able to solve these problems.  If there’s ever a chance to put a work-around in X-Plane, we do that.

So I can’t give you any new news on ATI Windows performance, and I am sorry about that.  I can only say that it is my top priority.

About Ben Supnik

Ben is a software engineer who works on X-Plane; he spends most of his days drinking coffee and swearing at the computer -- sometimes at the same time.

20 comments on “Meshes, Memory, Drivers, and Betas

  1. Ben, do you think a 64-bit X-plane would require plugin authors to port their .xpl’s to 64-bit as well, or could existing 32-bit plugins run under XPlane 64? Thanks RL

    1. I am 99% sure it will require plugins to be ported/recompiled. This is one of the reasons why the 64-bit change-over won’t be a total silver bullet. (Another reason is that some users have 32 bit operating systems, and reinstalling Windows isn’t much fun.)

      1. I’m totally optimistic that developers of the most used plugins, who are also some of the most active people around, will embrace 64-bit, too. It may take a while for “all green lights”, but hey, we all will benefit from 64-bit in the mid- and long-term!

      2. Actually reinstalling Windows is quite fun. Cleans up a messed registry etc.

        I find myself no reinstalling cr*p apps/games after reinstall, although I make sure to keep old profiles (for crucial parameters or save games etc.). System works fine for years now.

  2. I don’t believe the beer story Ben, that was Spain after all..

    I am hoping that RC2 fixes these bugs that have crept in but undermining my system at the moment…

    1) Extremely poor rendering of Custom Scenery (Since after 10.00b6 which was very good)

    2) Drop of extreme framerates with no change in view or custom scenery (OPENGL?)

    3) Weather gives very bad turbulence when downloaded (Now permanently turned off till fixed which is really annoying)

    I know post a bug report, but these three are getting pretty obvious….

    I am hoping Ben they are related to the article above.

    1. I think I’ve said this before but:


      Report bugs on the bug reporter. If you have not reported these, they will not get fixed. For example, I have _no_ bug reports that custom scenery has changed its rendering starting in 10.00b6. Please go file bugs now.

  3. well i’m not quite sure what changed either in 12.2 catalyst drivers, or with Xplane 10.04 rc, something broke. not only X-plane crashes now, but the whole computer. The whole ATI driver crashes and the computer gets a blue screen, then reboots. I had to rollback to a previous version of Catalyst for this NOT to happen.

    oh well. I still very much enjoy XP10 🙂

    1. That sounds to me like bad drivers – since 10.04 and 10.03 are _both_ available, please compare 10.04 vs 10.03 and cat 12-2 vs 12-1. Is there a pattern?

    2. I have been monitoring the Guru3D and AMD forums, and let me be the first to say that you are not alone. There’s something wrong with the newest Catalyst driver(s), which causes Windows to crash. I have received multiple BSODs since the March 7th update. I haven’t personally done this yet, but many have reverted to the previous release, which was stable. For the 7xxx series, some have recommended the RC11 drivers.

      Also, make sure you submit driver feedback to AMD:

  4. Worrying common themes emerging here- memory exhaustion, beer..
    I suspect the opposite is needed- any pics of u without a beer have been photoshopped!

  5. Does the latest executable have the large-address-aware flag on? If not, perhaps editbin /largeaddressaware can help?

    1. Yep – we’ve had large address aware on since X-Plane 9 or maybe even 8!! On win7/64 this means we get a full 4 GB, and since win7 drivers keep GPU resources out of process address space we do pretty well for resource usage. We see more problems on 32-bit OSes (3 GB max), and on Mac/Lin (where the drivers dump GPU resources into our address space).

      1. Thank you for the answer.

        Let me ask about one more thing – what’s problematic about 64-bit support? Is it sizeof(long) being 4 on 64-bit Windows? Or some issue unrelated to code quality?

        Anyway, great job on the sim – It’s nice to see it after the PC flight-simulator golden age is so long gone…

  6. Thank Ben – really enjoy your updates.

    I switched to Win 7 64 bit when I built a new computer. I really encourage anybody to make the switch to 64 bit OS sooner than later. Even though all my programs are 32 bit, the 64 bit OS does a wonderful job of using all of the 8gb of RAM I have on board – so X-plane can have all 4gbs and web browsers and other programs are pushed into other address spaces.

    Most drivers updated to 64 bit without problem – the only problem driver was for my scanner. The company would not release a 64 bit driver for it (probably the technology wouldn’t support it), so I had to buy a new scanner.

    1. Right!! – on win7-64 the limit for X-Plane is 4 GB – that’s the highest limit for any OS for a 32-bit app. And since the drivers often keep textures out of process address space, the driver is using less of our space too. The combination means that I pretty much never run my win7-64 machine out of memory.

      If you have a 32-bit windows install, think about 64-bit, because when we go 64-bit in the app, you’ll need the OS anyway!

  7. You never run out of address space, but there is never more memory than what the installed SIMMS provide.


Comments are closed.