Question regarding Scan speeds, with new HDD.

[Ddm5]

I'm planning on buying an SSD, 240GB which I'll be moving my OS to, with the usual scans being at 40Mb/s constantly when it slows down to the norm, will an SSD improve the scan speed with the OS being on that and most of the other things.
SSD: 550Mb/s read time.

[DavidR]

The HDD is the bottleneck in many systems and that would include scans. so moving to an SDD as your primary drive (for your OS and installed programs). This would be able to throw files at avast as quick as it can scan them, instead of there being times that avast is waiting for the HDD.

So there should be an appreciable difference.

[Ddm5]

The HDD is the bottleneck in many systems and that would include scans. so moving to an SDD as your primary drive (for your OS and installed programs). This would be able to throw files at avast as quick as it can scan them, instead of there being times that avast is waiting for the HDD.

So there should be an appreciable difference.

Even with me overclocking my I5 2500k to 4.5Ghz?, I should be quite pleased then.

[DavidR]

The CPU generally doesn't have a problem keeping up with an HDD during a scan, you only have to monitor the CPU activity in task manager to see that. So with an SSD the processor may be working a little harder, but I doubt it would trouble the i5-2500k.

Most of the avast scan defaults aren't to use the Highest Scan Priority, you might be able to bump this up a little.

[Ddm5]

The CPU generally doesn't have a problem keeping up with an HDD during a scan, you only have to monitor the CPU activity in task manager to see that. So with an SSD the processor may be working a little harder, but I doubt it would trouble the i5-2500k.

Most of the avast scan defaults aren't to use the Highest Scan Priority, you might be able to bump this up a little.

I use a high priority because it takes 45 minutes to scan 75Gb, and I don't have all my games yet, so yea..

[DavidR]

What type of scan are you doing ?

I don't know if you have the Scan Options set for using the Persistent Cache and particularly the 'Store data about scanned files in the persistent cache.' This is off by default I believe, whilst the 'Speed up scanning by using the persistent cache' is enabled by default but the second option helps populate the persistent cache for appropriate files.

[Ddm5]

What type of scan are you doing ?

I don't know if you have the Scan Options set for using the Persistent Cache and particularly the 'Store data about scanned files in the persistent cache.' This is off by default I believe, whilst the 'Speed up scanning by using the persistent cache' is enabled by default but the second option helps populate the persistent cache for appropriate files.

It's not enabled I think, but the scan I find to be weird, why does it spike to 500Mb/s and slowly decreases to 400, then to 150, then idles on 30 - 40 ?

[Gopher John]

When the scan is fastest, it is scanning files that are in Avast's transient or permanent cache.  When it gets to the unsigned files that are in neither cache, then the scan is at it's slowest. 

[DavidR]

What type of scan are you doing ?

I don't know if you have the Scan Options set for using the Persistent Cache and particularly the 'Store data about scanned files in the persistent cache.' This is off by default I believe, whilst the 'Speed up scanning by using the persistent cache' is enabled by default but the second option helps populate the persistent cache for appropriate files.

It's not enabled I think, but the scan I find to be weird, why does it spike to 500Mb/s and slowly decreases to 400, then to 150, then idles on 30 - 40 ?

You should enable it.

There will always variations during the scan, the reasons given by Gopher John are some of them.

You didn't say what scan this is as I asked ?
When you answer that, are any other changes to the default or scan settings you should also tell us that ?

If you are scanning archives and other large files, that will also slow scanning, personally I don't get concerned about the scan throughput whilst a scan is running. If I get curious I would do some arithmetic GB scanned divided by the scan duration, obviously it isn't a simple as that (convert GB to MB, convert duration to seconds) is a more accurate average scan throughput.

[Ddm5]

What type of scan are you doing ?

I don't know if you have the Scan Options set for using the Persistent Cache and particularly the 'Store data about scanned files in the persistent cache.' This is off by default I believe, whilst the 'Speed up scanning by using the persistent cache' is enabled by default but the second option helps populate the persistent cache for appropriate files.

It's not enabled I think, but the scan I find to be weird, why does it spike to 500Mb/s and slowly decreases to 400, then to 150, then idles on 30 - 40 ?

You should enable it.

There will always variations during the scan, the reasons given by Gopher John are some of them.

You didn't say what scan this is as I asked ?
When you answer that, are any other changes to the default or scan settings you should also tell us that ?

If you are scanning archives and other large files, that will also slow scanning, personally I don't get concerned about the scan throughput whilst a scan is running. If I get curious I would do some arithmetic GB scanned divided by the scan duration, obviously it isn't a simple as that (convert GB to MB, convert duration to seconds) is a more accurate average scan throughput.

Ahh, It's storing the persistent cache, but isn't reading it, I'll enable it, I've ordered my SSD aswell so I can't wait to get that and put that to the test. All the settings are on full for the "Full system scan" Which I do roughly every week or so.

[DavidR]

The reading/using the persistent cache should make a big difference after a few scans.

[Ddm5]

The reading/using the persistent cache should make a big difference after a few scans.

I bet, I mostly just do quick scans anyway.

[Ddm5]

The reading/using the persistent cache should make a big difference after a few scans.

A bit late, but owell, screenshot of average scan speed, Mid scan -> end, being 145 - 155Mb/s

[DavidR]

A massive difference, given your previous post "I use a high priority because it takes 45 minutes to scan 75Gb." Though this is for slightly less GB scanned 56.5GB in 6 Min 41 Sec.

[Ddm5]

A massive difference, given your previous post "I use a high priority because it takes 45 minutes to scan 75Gb." Though this is for slightly less GB scanned 56.5GB in 6 Min 41 Sec.

x5 The scan speed with the SSD, boot time is a lot faster aswell, Start of the scan spikes to 1.6Gb/s, quite happy.