Long pause before iTunes selection plays?
Is this behavior normal?
I can doubleclick on a song stored on my HD or a song on a CD that has already been in the drive and mounted, but there is always an unbearably long pause before any sound starts playing (and iTunes is unresponsive to any further input until it does start playing sound). WTH is it doing in there? I can pop a CD into my home player, hit play, and boom, I'm playing music in less than a second. So what's going on inside there that is so taxing?
I can doubleclick on a song stored on my HD or a song on a CD that has already been in the drive and mounted, but there is always an unbearably long pause before any sound starts playing (and iTunes is unresponsive to any further input until it does start playing sound). WTH is it doing in there? I can pop a CD into my home player, hit play, and boom, I'm playing music in less than a second. So what's going on inside there that is so taxing?
Comments
If that ain't enough, then I'd say Apple has beat a bloated M$ product at their own game!
OS 9 memory management is just fine. Certainly not as sophisticated as OSX, but it's certainly capable of doing the basic task. I can open and close apps all day and not "run out of memory because it has not been released". It "releases" just fine on my machine. Perhaps some erratic behavior can crop up when you extend yourself a good deal into virtual memory, but that's easy to fix (add more memory) if you are really using that much. At 384 MB, my needs are well covered w/o extending into VM at all.
1) locate the file. (ridiculously fast)
2) open the file. (also, quite fast)
3) read in (part of) the file (this is probably the most taxing, depending on how much of the file iTunes is "buffering"; i don't know if its configurable. i'm pretty sure that hard drives are the slowest part of a computer's hdwr)
4) convert the (part of the) file to raw audio data (this can also be a time consumer, depending largely on the format of the file, the length of the buffer, the speed of the proc, and probably other things)
5) pass the raw audio to the speakers (ridiculously fast)
iTunes generally tries to make up for the potential speed hit in (my listed) step 3, by reading in the next file(s). it can't avoid going the whole rigamarole on the first run, so it makes up for it during play. it will convert several files' data to raw audio, and pass it along to the speaker as is needed. generally, reading and converting the mp3s to raw is faster than real time, so its not too much of a problem; you only notice it in the beginning. and, by grabbing data ahead of the live audio, it prevents this from being a consistent problem. but when you pop in a cd (or when you open iTunes fresh, or suddenly play songs from your list), iTunes has to forsake its old buffer, and fill it with the cd's (or your selected song's) data. so its going merrily along its way, locating files, reading them, filling its buffer, converting, waiting for the speakers to catch up, and you suddenly say, "hey, forget all that work you just did. go here." the computer at this point obidiently obeys your command, but has to make up for all that potential time saving it was doing earlier.
now, the delay you experience shouldn't be too much. for me its something like 1 second or something. noticeable, but small. if its much more than that, it could be: a slow hard drive, low RAM, other programs using up the processor (therefore taking cycles away from all of iTunes' steps), slow proc, old proc, or probably a large number of other things that i can't think of right now.
Here's what I am experiencing:
starting a track- 11 sec
pausing, then restarting- 11 sec
NOTHING else that runs on my computer displays control latency on that order- just the audio from iTunes and the CD player console. If I'm doubleclicking a short sound bite file for Quicktime, even that runs right on the mark.
The iTunes memory allocation is currently set at the default 6144 kB. Anybody think it could benefit from a higher setting? Yeah, I could just try it and see, but what in the world would justify it needing that much memory to run properly?
EDIT: Just dragged the AIFF file directly into Quicktime. The control seems to be quite responsive just like playing video. So what's the deal with iTunes then?
Originally posted by Randycat99
starting a track- 11 sec
pausing, then restarting- 11 sec
ok, thats a lot longer than i thought.
The iTunes memory allocation is currently set at the default 6144 kB. Anybody think it could benefit from a higher setting? Yeah, I could just try it and see, but what in the world would justify it needing that much memory to run properly?
jeez. i forgot about classic memory management. i'm not sure exactly how much you should make it, but definitely more than 6144 kB. All that RAM you have isn't being used by iTunes, its only using 6MB. The raw audio data is roughly on the magnitude of 10M/minute. I can't remember how much memory iTunes or any other mp3 player has used. iirc, my itunes would use approximately 30MB. I'm guessing that iTunes is trying to buffer a large part of the file, and convert and save that data in memory, but is paging out like a wicked monster.
how much memory is allocated for quicktime?
Originally posted by Randycat99
My Quicktime is set to 8.1 MB. Even if it was the impact of memory allocation, I don't see a mere 2 MB difference making 11 sec worth of improvement. If anything, if Quicktime can whiz video around with 8 MB of memory allocation, iTunes shouldn't need much more than a single MB to do the actual task of music playing, IMO.
well, qt and itunes have very different guis. iTunes keeps an in memory list of your library, and each of your playlists. i presume it also keeps all the metadata in memory. all that stuff adds up. qt will only keep the file it is working on in memory (and maybe not even the whole file). try making itunes' ram unusually high. like preferred ram size=100MB. quit all unused apps, and then open iTunes. see if that makes a difference. then slowly scale back how much memory you give iTunes.
Old drives can cause rather unpredictable results. Complete multi-minute lockups (at least for me in 10.2.x), hung programs, hung IO to all devices... the list could go on and on. One of these is extremely slow access to all or a select few files.
Originally posted by dfiler
If you're talking about playing audio from a CD, a failing cd-drive can easily produce these symptoms. It can take forever (in computer terms) for a drive to spin up and repeatedly fail to track...
Hmmm, this is a interesting theory. However, my old DVD drive seems to be able to mount discs and access files on CDROM/CDR/CDRW's in a reasonably short moment. The behavior is the same with my newer USB CD burner drive. The drives do not seem to show any signs of distress when used by other programs, yet iTunes takes excruciatingly long times to get a song going whether it comes from a disc or the HD. This really something to do with iTunes specifically, IMO.