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How to speed up the write speed of HDD


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To all those computer wizards out there. I wonder if it is possible to increase the write speed of my HDD. Yes I know I need a external SSD drive. But can not afford a good one  at this time.

I have been testing my ASI 290MM on both sharpcap and firecapture. And the problem really resides at full resolution, as soon as I start doing smaller ROIs it speeds up a lot.

As soon as the capture starts using USB 3 on sharpcap for example, it runs at full speed for about 8 secs, then the dropped frames start kicking in, and I am getting just over half the frames I could be.

It seems like a bottle neck where the HDD just can not keep up with the data transfer. I have a 1TB.  8 GIG RAM.  Intel Core i3 CPU

in one minute on average, I am getting around 2600 frames at the full resolution of the ASI 290 chip around 43 frames a second. The camera can kick out 82 FPS the extra are just getting dropped.

I know I wont cure this problem without SSD, but can I find ways to squeeze more out of the HDD. The best frame count I got after defragging, and playing with buffering on Firecapture was 3300

in one minute at full res. high speed setting clicked makes it slightly slower ? usb traffic set to 80

With serious ROI cropping this laptop has run at 600 FPS.  So its the 2.1Mega Pixels 1936×1096 ZWO chip that the laptop is struggling most with

 

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Don't know if it will help you but I use Firecapture and capture directly to Seagate 1tb extenal USB drive, about £50.00 from various places.

I also do all the processing on it and just download finished Tiffs to my HD.

Dave

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I had similar problems with the older, family  laptop.  The first 500-odd frames the ASI178MM runs flat-out, because the data are stored in memory (a disk buffer), or on a memory cache in the HDD itself. After that time the frame rate dropped. That laptop has only one USB 3.0 port, so I could not attach anything externally that could keep up with the data rate.  It may be possible to extend the buffer sizes to capture more data quickly.

I have now got a laptop with 3 USB 3.0 ports, and a (smallish) internal SSD. The latter is really too small for solar and lunar mosaics, so I do not use it for capture. Instead, I use an external USB 3.0 500GB SSD, which speeds things up dramatically. It is the Samsung T1, which does not come cheap, but if you have at least two USB 3.0 ports on the laptop it does work wonders. It is really tiny compared to a regular external HDD

IMAG0663.jpg

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2 hours ago, michael.h.f.wilkinson said:

I had similar problems with the older, family  laptop.  The first 500-odd frames the ASI178MM runs flat-out, because the data are stored in memory (a disk buffer), or on a memory cache in the HDD itself. After that time the frame rate dropped. That laptop has only one USB 3.0 port, so I could not attach anything externally that could keep up with the data rate.  It may be possible to extend the buffer sizes to capture more data quickly.

I have now got a laptop with 3 USB 3.0 ports, and a (smallish) internal SSD. The latter is really too small for solar and lunar mosaics, so I do not use it for capture. Instead, I use an external USB 3.0 500GB SSD, which speeds things up dramatically. It is the Samsung T1, which does not come cheap, but if you have at least two USB 3.0 ports on the laptop it does work wonders. It is really tiny compared to a regular external HDD

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Hi Michael I have the same problem I clearly am not thinking the problem through correctly, as I only have one USB 3 port as well. So even a external SSD is out on this laptop I guess

I don't suppose any external SSD would have usb 3 inputs that the camera could go into and then connect to a laptop. I am guessing it can't work that way

How could I go about extending the buffer size if that's my only option Michael

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In FireCapture there is some setting for the RAM buffer. Explanations are found here:

http://www.wonderplanets.de/FireCapture/help/settings.html

 

It says it is experimental, but I have used it, and it did help a bit, but the limited memory of the laptop I was using limited its use. I think FireCapture is written in Java, so you have to set the memory limit. Make sure you are using 64-bit Java or you are stuck with a maximum of 4 GB. More can be found here:

http://stackoverflow.com/questions/1493913/how-to-set-the-maximum-memory-usage-for-jvm

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I might have missed it but if you are using a PC as opposed to laptop, you can get solid state hard drives on s card which use standard dimm memory. They are only of use whilst powered so in a case of power failure you loose all the data. But for temporary storage from a camera they are fine. The info can be spread over a raid array of cheap hard drives. This method is very fast but volatile.

Derek

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13 hours ago, Physopto said:

I might have missed it but if you are using a PC as opposed to laptop, you can get solid state hard drives on s card which use standard dimm memory. They are only of use whilst powered so in a case of power failure you loose all the data. But for temporary storage from a camera they are fine. The info can be spread over a raid array of cheap hard drives. This method is very fast but volatile.

Derek

Hi Derek No sorry its a laptop

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The only really successful method is to replace the hard drive with an SSD then. Do not try the HYBRID TYPES ! They are useless. I bought 7 of them and all slow down over time. They cannot handle large amounts of continuous data input either. There buffer SSD just fills up. Samsung Pro 850 SSDs  are the best I have used. Got one in my PC and Laptop. Going to put in a couple of 2Tbs shortly when funds allow. I am using 4 Hybrid drives in a 1,0 array in the Pc and they have slowed right down.

Sorry but SSD all the way.

Some newer Laptops can take the Samsung 950 SSD cards but there are two competing types the Fast M.2 SATA SSD and the mini  PCIe.

Both can suffer from overheating, but the M2 is better in that respect as far as I am aware.

Derek

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On 1 July 2016 at 12:34, neil phillips said:

I have been testing my ASI 290MM on both sharpcap and firecapture. And the problem really resides at full resolution, as soon as I start doing smaller ROIs it speeds up a lot.

As soon as the capture starts using USB 3 on sharpcap for example, it runs at full speed for about 8 secs, then the dropped frames start kicking in, and I am getting just over half the frames I could be.

It seems like a bottle neck where the HDD just can not keep up with the data transfer. I have a 1TB.  8 GIG RAM.  Intel Core i3 CPU

in one minute on average, I am getting around 2600 frames at the full resolution of the ASI 290 chip around 43 frames a second. The camera can kick out 82 FPS the extra are just getting dropped.

I know I wont cure this problem without SSD, but can I find ways to squeeze more out of the HDD. The best frame count I got after defragging, and playing with buffering on Firecapture was 3300

in one minute at full res. high speed setting clicked makes it slightly slower ? usb traffic set to 80

With serious ROI cropping this laptop has run at 600 FPS.  So its the 2.1Mega Pixels 1936×1096 ZWO chip that the laptop is struggling most with

 

I think you have several bottlenecks and your HDD is one of them.

Your camera image is about 3 MegaBytes (MB) but depending on the transfer protocol may send 4MB across the link.  let's assume 3MB per image; At 82FPS that's approx 240MB per second about 2 gigabits/sec. Around 40% USB3 theoretical capacity. Your laptop may not be able to sustain that transfer speed which is why you drop to 43 frames per second whilst you buffer the data in RAM.

So at 43 FPS you need a disk with a sustained write speed of at least 120MB/sec. (240MB/sec for the full 82FPS. But I suspect other bottlenecks will appear.)

You do not say which laptop you have?  Can you change out the internal drive?  Using an external drive may not provide the result you are looking for as the USB3 bandwidth will be shared between your camera and the ext disc.

Can you increase the RAM in the laptop to get an extra minute of data?

So to answer your original question your best bet is to replace the internal disc with whatever SSD you can afford that has a sustained write speed better than 120MB/S

Andy

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A search on this site will give you more details about the internals of your laptop,

http://h10032.www1.hp.com/ctg/Manual/c05078936

If this is the manual for your laptop (you have not said which generation of I3 is fitted) then it shows how to change the internal drive or even fit an M.2 SSD.  A 500GB SAMSUNG evo 850 costs about £140 and has good performance reviews.

Andy

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