Solve : slow file copy many files?

1.	Solve : slow file copy many files?
Answer» Slow file COPY when there are many files from revo drive to usb 3 drives (several usb 3 flash drives brand new). Why? I recieve about 5MB per second when copying 13,000 files to the drive all different size files and the total size transfered is about 7GB. Why do I get 5MB per second? I get 180MB/sec average from revo to SSD (same files) I also get 50MB/sec from revo to USB3 Hard drive (not flash drive) (same files) LASTLY I get 30-50MB/sec from same flash drives when copying a smaller amount of files. Is it something to do with FAT32 file system on a flash drive with many files? My info: Operating System: Windows 7 Ultimate 64-bit (6.1, Build 7601) Service Pack 1 (7601.win7sp1_gdr.110622-1506) Language: English (Regional Setting: English) System Manufacturer: To Be Filled By O.E.M. System Model: To Be Filled By O.E.M. BIOS: BIOS Date: 06/22/11 21:13:12 Ver: 04.06.04 Processor: Intel(R) Core(TM) i7-2600K CPU 3.40GHz (8 CPUs), ~3.4GHz Memory: 16384MB RAM Available OS Memory: 16366MB RAM Page File: 2361MB used, 16003MB available Windows Dir: C:\Windows DirectX Version: DirectX 11 DX Setup Parameters: Not found User DPI Setting: 120 DPI (125 percent) System DPI Setting: 96 DPI (100 percent) DWM DPI Scaling: Disabled DxDiag Version: 6.01.7601.17514 32bit Unicode video: 2 GTX560TI SLI [year+ old attachment deleted by admin]try the Tera Copy software and see if it does any better for you.nope still 5MB/sec...aroundI think 5MBps is pretty average for a USB stick. Don't expect anything faster unless you bought a high-end model.It is a high end model. it says its read is 54MB/SEC It says its Write is 20MB/sec My ACTUAL write is 5MB/sec with that amount of files. My actual write SPEED with one big file is about 40MB/sec the highest. Why does the speed lower if I have many files? Quote It says its Write is 20MB/sec That speed is a theoretical maximum, and probably measured using one large file. Flash memory write speeds will be slower for many small files. The reason is that although flash memory can be read or programmed a byte or a word at a time in a RANDOM access fashion, it can only be erased a "block" at a time. This generally sets all bits in the block to 1. Starting with a freshly erased block, any location within that block can be programmed. However, once a bit has been set to 0, only by erasing the entire block can it be changed back to 1. In other words, flash memory (specifically NOR flash) offers random-access read and programming operations, but cannot offer arbitrary random-access rewrite or erase operations. Transferring multiple small files, especially if many are smaller than the chip-specific block size, could lead to a much lower rate than the maximum rate measured using large files, as you have noticed.

Answer»

Slow file COPY when there are many files from revo drive to usb 3 drives (several usb 3 flash drives brand new). Why? I recieve about 5MB per second when copying 13,000 files to the drive all different size files and the total size transfered is about 7GB. Why do I get 5MB per second?

I get 180MB/sec average from revo to SSD (same files)
I also get 50MB/sec from revo to USB3 Hard drive (not flash drive) (same files)
LASTLY I get 30-50MB/sec from same flash drives when copying a smaller amount of files.
Is it something to do with FAT32 file system on a flash drive with many files?

My info:

Operating System: Windows 7 Ultimate 64-bit (6.1, Build 7601) Service Pack 1 (7601.win7sp1_gdr.110622-1506)
Language: English (Regional Setting: English)
System Manufacturer: To Be Filled By O.E.M.
System Model: To Be Filled By O.E.M.
BIOS: BIOS Date: 06/22/11 21:13:12 Ver: 04.06.04
Processor: Intel(R) Core(TM) i7-2600K CPU 3.40GHz (8 CPUs), ~3.4GHz
Memory: 16384MB RAM
Available OS Memory: 16366MB RAM
Page File: 2361MB used, 16003MB available
Windows Dir: C:\Windows
DirectX Version: DirectX 11
DX Setup Parameters: Not found
User DPI Setting: 120 DPI (125 percent)
System DPI Setting: 96 DPI (100 percent)
DWM DPI Scaling: Disabled
DxDiag Version: 6.01.7601.17514 32bit Unicode
video: 2 GTX560TI SLI

[year+ old attachment deleted by admin]try the Tera Copy software and see if it does any better for you.nope still 5MB/sec...aroundI think 5MBps is pretty average for a USB stick. Don't expect anything faster unless you bought a high-end model.It is a high end model. it says its read is 54MB/SEC
It says its Write is 20MB/sec

My ACTUAL write is 5MB/sec with that amount of files. My actual write SPEED with one big file is about 40MB/sec the highest.

Why does the speed lower if I have many files? Quote

It says its Write is 20MB/sec

That speed is a theoretical maximum, and probably measured using one large file. Flash memory write speeds will be slower for many small files. The reason is that although flash memory can be read or programmed a byte or a word at a time in a RANDOM access fashion, it can only be erased a "block" at a time. This generally sets all bits in the block to 1. Starting with a freshly erased block, any location within that block can be programmed. However, once a bit has been set to 0, only by erasing the entire block can it be changed back to 1. In other words, flash memory (specifically NOR flash) offers random-access read and programming operations, but cannot offer arbitrary random-access rewrite or erase operations. Transferring multiple small files, especially if many are smaller than the chip-specific block size, could lead to a much lower rate than the maximum rate measured using large files, as you have noticed.

Solve : slow file copy many files?

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