Recommended block size

[WebMaximus 372]

Anyone in here tried playing around with different disk block sizes to see how performance is affected?

Since a while back I'm using XP11 as my main flight sim and this with Ortho4XP photo scenery covering the major part of Europe. I have a dedicated a 10 TB 7200 RPM HDD for the photo scenery which takes up about 6 TB of the drive.

One thing I've noticed is how some stuttering occurs when new photo scenery is read as you fly along.

For this reason I started thinking that maybe increasing the block size from the standard 4096 bytes to something bigger, maybe even all the way up to 2MB, might increase performance. This based on the fact that the average file size for this drive is 4.3 MB where 4096 bytes blocks doesn't seem very efficient.

What do you guys think?

[ryanbatc 12,836]

I think if you can put it on a SSD you'll be better off hehe.  I also get the stutters I've got mine on my 1TB 7200 rpm hdd.

[Bob Scott 7,720]

I would guess that XP does lookahead scenery buffering much like the ESP-based platforms do, which means the scenery elements should already be loaded in RAM when time comes to render them in a frame.  If so, that would suggest the stutters are more likely related to pushing the large bitmaps to the video card from system memory, making modest changes in HDD throughput pretty much irrelevant.  Fast RAM (system and GPU) and a high-bandwidth PCIe bus would probably be the place to look for improvements there.

Regards

 

[WebMaximus 372]

3 hours ago, ryanbatcund said:

I think if you can put it on a SSD you'll be better off hehe.  I also get the stutters I've got mine on my 1TB 7200 rpm hdd.

Getting an SSD (or a couple of SSDs) to store some 6 TB data might end up being a bit too expensive for my taste 😄

2 hours ago, w6kd said:

I would guess that XP does lookahead scenery buffering much like the ESP-based platforms do, which means the scenery elements should already be loaded in RAM when time comes to render them in a frame.  If so, that would suggest the stutters are more likely related to pushing the large bitmaps to the video card from system memory, making modest changes in HDD throughput pretty much irrelevant.  Fast RAM (system and GPU) and a high-bandwidth PCIe bus would probably be the place to look for improvements there.

Regards

 

What you say is interesting but I'm not sure that is the case here. Reason being I see the disk activity light glowing at the same time I experience the stuttering.

Looking at the other parts of my system, I don't have a top of the line system but still fairly competent - a 6700K @ 4.5 GHz, 16 GB 3000 MHz DDR4 RAM and a 1080Ti. My system as well as XP partitions reside on a Samsung 950 Pro SSD.