Audacity Forum

Hi all!
i just found a little problem with audacity 1.3.13-beta.
i'm using it on a windows 7 64 bit with 8 GB of ram.
as you know, x64 system allocate a maximum of 2GB of memory for a single 32 bit process.

if i set audacity to record on RAM, it partially hangs when it reach this limit.
recoding in 96000Hz stereo 24-bit PCM occours after 35-38 minutes.

in this condition, you are able to use some control but you cannot save project or export your record.

nushuth wrote:if i set audacity to record on RAM,

Do you mean:
Edit menu > Preferences > Directories > Audio cache: "Play and/or record using RAM (useful for slow drives)"

That option is really just a workaround for users with very old or slow machines. In all other cases that option should be disabled.
There are some major disadvantages with recording to RAM, one of which is that in the event of a crash all data will be permanently lost.

Also I would recommend that you set the recording quality to 32-bit float as this allows virtually perfect precision when editing/processing.

thank you for your answer.

i mean exactly that... and i record disabling it.
i wrote my thread only to report this issue to developer team..

but there is another little advantage using this option:
in some HW configuration, expecially with notebooks, HDD drive activity may generate some electro-magnetic field wich cause noise in recording. recording to ram prevent this issue. that's why i would try to use that option enabled...

Moved to Windows 1.3 forum because this is Windows specific discussion

nushuth wrote: as you know, x64 system allocate a maximum of 2GB of memory for a single 32 bit process.

That's true on 32-bit systems, but not on 64-bit as I understand it:
http://blogs.technet.com/b/markrussinov ... 55406.aspx

Because the address space on 64-bit Windows is much larger than 4GB, something I’ll describe shortly, Windows can give 32-bit processes the maximum 4GB that they can address

nushuth wrote: if i set audacity to record on RAM, it partially hangs when it reach this limit. recoding in 96000Hz stereo 24-bit PCM occurs after 35-38 minutes.

According to my calculations, at 96000 Hz 24-bit stereo you use about 32.7 MB of space per minute, so you have about an hour of recording available before you use 2 GB. You are hitting some other limit, it would seem.

As your results suggest, the "Audio Cache" feature seems to produce issues in practice once large amounts of memory are used, even if the machine suggests spare RAM is still available. Audacity should start writing to disk again once the available RAM falls below a certain level (16 MB by default), but problems seem to occur before that availability limit is reached.

However I think you would have to test by granting other applications on the same machine 1 GB of RAM or more before you could say this is an Audacity problem or a practical problem with the machine or with Windows.

Although writing to RAM should be faster and possibly "cleaner", it's risky. It may be better not to risk it unless your drive is so slow that there is a greater risk of dropouts. If HDD noise is a problem, the better solution may be an external sound device.




Gale