Hi!

I upgraded the player with piggyback memory chips and installed 2.01.

Now that I have a lot of memory, I was anxious to see the improvement in HDD running time. I did some testing, with both 16 and 32meg.

To my surprise, the HDD are spinning the exact same timeover a specific period, say 1 hour, both with and without the memory upgrade. What's the difference? The number of time they have to spinup. The improvement there is impressive. If I don't skip, the HDD can be stopped for about 30 minutes before being requested again.

My question concern the time required to cache the songs into memory. During the tests I did, at every startup, the HDD are spinning for about 1minute, sometimes up to 1:30. I'm wondering if it's normal. I find it quite slow: about 25meg transfered in 1:15 = 350k/sec. Is it normal?

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After a check, the maximum download rate I can achieve through ethernet via http is 320k/s. I guess I'm spoiled by recent computers' HDD and though it could be as fast in the empeg. But wait, why do I upload at about 750k/s to the empeg with emplode. Is the player app taking that much processing power?

Thanks for your input

There's no DMA controller in the empeg. All disk activity is handled by the CPU.

The reading from disk is done slowly, since it's all PIO (done by the CPU itself), which takes away from playing of music without skipping. With Hijack installed, it's done even more slowly, so as not to lock out the UI (which is what happens with 32MB and a stock kernel..).

No fuss. It's the spin up/down that hurts drives the most.

Cheers

ISTR we were getting at least 2MB/sec (maybe even up to about 4MB/sec) when nothing else was happening. But as has been said, there's no DMA controller in the empeg and so it's all done by steam.

The SA1110 had some more bits that could be twiddled to shorten IO cycles on external devices which meant we got more like 6MB/sec, but the SA1100 in the empeg lacks this. The PXA255 (successor to the StrongARM line) manages more along the lines of 10MB/sec and also has support for external DMA.

Later chips with built in ATAPI interfaces can pretty much saturate the disk drive - 30+ MB/sec.

Hugo