Activity › Forums › Storage & Archiving › Windows file copy is tremendously slow
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Windows file copy is tremendously slow
Posted by Irrani Dam on November 3, 2009 at 1:31 amHi,
I’m copying a large database file (23GB) from one mounted iSCSI
volume
to another. It’s taking over an hour to copy. Network utilization and
CPU on the host and iSCSI server are fine.
The MegaRaid perfomance monitor on the iSCSI box(storage
concentrator)
shows the disk activity in waves:
10MB/sec at 200 “I/O”/sec
then
4000KB/sec at 60 “I/O”/sec
Devices are connected via a single gigabit ethernet connection each,
via a Cisco 3750 switch. They are the only active hosts on a storage
VLAN.
Any suggestion or recommendation to speed up the copy function.IrrANI
Keren Aarons replied 16 years, 6 months ago 3 Members · 2 Replies -
2 Replies
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Edwards Willeam
November 4, 2009 at 1:15 amHi Irrani,
Have you tried nic porting? What I mean is using multiple network
ports in parallel to increase the link speed beyond the limits of any
port.
Also please try below steps.
LSI MegaRAID performance tuning; controller policy for RAID-1 vs
RAID-5
Performance of various RAID levels
What is the relative performance of the different RAID levels?
Symptom
Not sure what settings to use with the different RAID levels
available
Fact
Variable environments, Intel, AMD platforms
Fix
LSI Logic MegaRAID controllers are designed to provide the best
performance throughput. They support a number of policies:
* Write policy – Write Through (WT) and Write Back (WB)
* Read policy – Read Ahead (RA), No Read Ahead (NRA) — also called
normal, and Adaptive Read Ahead (ARA)
* Cache policy -Direct I/O (DIO) and Cached I/O (CIO)
The following are the 12 ways that LSI Logic MegaRAID controllers can
be configured:
WB, NRA, DIO WB, RA, DIO WB, ARA, DIO
WB, NRA, CIO WB, RA, CIO WB, ARA, CIO
WT, NRA, DIO WT, RA, DIO WT, ARA, DIO
WT, NRA, CIO WT, RA, CIO WT, ARA, CIO
Write Policy
*
Write-Through Cache In Write-through caching, the controller sends a
data transfer completion signal to the host when the disk subsystem
has received all the data in a transaction. This caching strategy is
considered more secure, since a power failure will be less likely to
cause loss of data. The default setting is Write-Through.
*
Write-Back Cache In Write-back caching, the controller sends a data
transfer completion signal to the host when the controller cache has
received all the data in a transaction. Because the magnetic media is
slower than the cache, write-back caching allows the operating system
to move on to other tasks more quickly, improving overall system
performance. In write-back cache, data is written to the disk when it
is forced out of controller cache memory or forced out by the flush
timer. An optional battery backup can be used to protect data in the
cache against data loss as a result of a power failure or system
crash.
Read Policy
* Read-ahead Read-Ahead capability allows the adapter to sequentially
read ahead of requested data and store the additional data in cache
memory, anticipating that the data will be needed soon.
* No-Read-Ahead Only the requested data is read and the controller
does not read ahead.
* Adaptive specifies that the controller begins using read-ahead if
the two most recent disk accesses occurred in sequential sectors. If
all read requests are random, the algorithm reverts to No-Read-Ahead;
however, all requests are still evaluated for possible sequential
operation..
Cache Policy
*
* Cached I/O Cached I/O option specifies that all reads and writes
are
buffered in cache memory. Data is transferred to cache and the host
concurrently. If the same data block is read again, it comes from
cache memory.
Direct I/O Direct I/O specifies that reads and writes are not
buffered
in cache memory. Direct I/O does not override the read policy
settings.
Recommended Settings for the best Performance:
*
For RAID 0: Write Through, No Read Ahead (Normal), Direct I/O
*
For RAID 1: Write Through, No Read Ahead (Normal), Direct I/O
*
For RAID 5: Write Back, No Read Ahead (Normal), Direct I/O
Note
The information provided here is intended to assist you in finding
the
optimum settings for your application of the product. The settings
that works best for you may not always be the same in different
environmentsRegds,
Dufrence -
Keren Aarons
November 15, 2009 at 2:45 pmHi
I think I have a much easier solution. Try this program: https://www.codesector.com/teracopy.php
It sped up my file copying by 200 – 300% in Windows 2000 and Xp. We were having to digitise online footage onto other media drives and then copy them across 150 – 250 gigs a time and this program saved our life.
Let me know if it works.
Cheers
Keren
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