Windows SSD Speeds - why so slow???
Discussion
I am using a very high end Dell laptop supplied by my current client. It cost considerable more than a Macbook Pro....
SSDs should be fast. Looking at some of the benchmarking sites (https://www.tomshardware.com/features/ssd-benchmarks-hierarchy) even a slow one should be able to handle file copy at speeds greater than 800MB/s
So why does it take forever and a day to copy a 10Gb build/source code directory?
The only reasons I can come up with are:
1: Virus Scanner
2: The underlying Windows kernel (based on DOS
) is just slow
SSDs should be fast. Looking at some of the benchmarking sites (https://www.tomshardware.com/features/ssd-benchmarks-hierarchy) even a slow one should be able to handle file copy at speeds greater than 800MB/s
So why does it take forever and a day to copy a 10Gb build/source code directory?
The only reasons I can come up with are:
1: Virus Scanner
2: The underlying Windows kernel (based on DOS
) is just slowbudgie smuggler said:
- Virus scanner, temporarily white list the directory and see if it is now fast
- Source directories are typically thousands of small files, pretty much the worst case scenario for filesystem performance
- The drive may be formatted with the partitions incorrectly aligned
Files are not in use while copying ...- Source directories are typically thousands of small files, pretty much the worst case scenario for filesystem performance
- The drive may be formatted with the partitions incorrectly aligned
The machine was configured / formatted by Dell so I would hope they know what they are doing, but I wouldn't ne surprised if they don't...
As the directory is the source + build of a very large C++ project it will be many thousands of small files so I guess combined with the virus scanner that could be the cause (Virus scanners are generally poorly written often spawning 1000s of threads when they should spawn 1 per core max).
Unfortunately there is no way to "Whitelist" a directory due to it being outside of my control - we also have a build server running Jenkins which regularly fails due to a file being locked, probably by the virus scanner (the classic DOS big file lock). I have tried Windows Powershell (and PowerToys - FileLockSmith) to check the file but they either report the file is not locked or simply lock up.. IT's only solution is the classic reboot which is piss-poor for a build server running CD/CI.
Where are you copying the source data from?
It used to be that SSD were only faster than HDD in specific scenarios - ie long sequential reads of well organised data writes, but certainly lots of small files is always going to be a "slow" copy no matter what the medium, that and AV getting in the way.
It used to be that SSD were only faster than HDD in specific scenarios - ie long sequential reads of well organised data writes, but certainly lots of small files is always going to be a "slow" copy no matter what the medium, that and AV getting in the way.
jesusbuiltmycar said:
Further investigation reveals that it is Windows specific. A similar copy on a Linux VM (running on the same machine) is orders of magnitude quicker....
Assuming it's NTFS, ensure last access time is disabled for the volume. (Linux distros mostly ship with relatime enabled, so only update the atime when the mtime is altered). Fsutil is the command you want, but you would need admin privs to make the change.
But I still think it's more likely to be mostly slower from the virus scanner.
Have you tried
FastCopy - https://fastcopy.jp/
or
TeraCopy - https://www.codesector.com/teracopy
or even good old
RoboCopy - https://learn.microsoft.com/en-us/windows-server/a...
FastCopy - https://fastcopy.jp/
or
TeraCopy - https://www.codesector.com/teracopy
or even good old
RoboCopy - https://learn.microsoft.com/en-us/windows-server/a...
Windows Explorer in Win11 has cack copy processes. As pointed out, robocopy or xcopy if you're able.
Also use this tool to examine how your speeds are: https://www.grc.com/readspeed.htm
Also use this tool to examine how your speeds are: https://www.grc.com/readspeed.htm
Is Bitlocker enable on the drive?
This is the default drive encryption and can slow down data transfer speeds.
https://www.pcworld.com/article/2113846/default-wi...
This is the default drive encryption and can slow down data transfer speeds.
https://www.pcworld.com/article/2113846/default-wi...
simon_harris said:
Where are you copying the source data from?
It used to be that SSD were only faster than HDD in specific scenarios - ie long sequential reads of well organised data writes, but certainly lots of small files is always going to be a "slow" copy no matter what the medium, that and AV getting in the way.
This, its likely 10gb of source code is 1000s or 100,000s of small files, which is always going to take way longer than a single 10gb file.It used to be that SSD were only faster than HDD in specific scenarios - ie long sequential reads of well organised data writes, but certainly lots of small files is always going to be a "slow" copy no matter what the medium, that and AV getting in the way.
essayer said:
Explain to someone senior at the client that this is costing them £££… they will assist you in finding a competent IT person to whitelist the build/src dirs
A 'competent IT person' would do the duplication outside of hours or find another solution such as hosting the files somewhere suitable to begin with.Alot of ssd's are slow once the ram cache is full,.
Tiny files are slow to be written and QLC chips are slow, They also get pretty hot, not something you want in a laptop.
Have a read of the replies on this post,
https://www.reddit.com/r/hardware/comments/14dvxsn...
Tiny files are slow to be written and QLC chips are slow, They also get pretty hot, not something you want in a laptop.
Have a read of the replies on this post,
https://www.reddit.com/r/hardware/comments/14dvxsn...
Gassing Station | Computers, Gadgets & Stuff | Top of Page | What's New | My Stuff