TalkChess.com

How well would something like this work for storing the Syzygy WDL files?

https://www.visiontek.com/solid-state-d ... etail.html

Other suggestions welcome. I'm looking for a Linux-friendly, external USB 3 option, preferably bus-powered. Thanks.

If these read & write speeds are real..well then you have a good one.

Just compare them with real benches..search in youtube!

JP.

Looking good!

https://www.youtube.com/watch?v=AjYbOMf93Rk

thanks for sharing this link louis, havent heard of these. may pick one up myself & swap the wdl for a game or two when not chessing

zullil wrote:How well would something like this work for storing the Syzygy WDL files?

https://www.visiontek.com/solid-state-d ... etail.html

Other suggestions welcome. I'm looking for a Linux-friendly, external USB 3 option, preferably bus-powered. Thanks.

This has the same performance with a lower price.

http://www.newegg.com/Product/Product.a ... -_-Product

It's also available in sizes of 60GB and 240GB.

Regards,

Forrest

Check on youtube..for sure not so good this Mushkin Enhanced Ventura Ultra 120GB!

https://www.youtube.com/watch?v=MIGDkpQwYpc

You need to check real life benches!

JP.

These are sequential read/write speed.

For Syzygy it's meaningfull. Latency (access time), I/O per second only matters.
Compare to ATA interface (DMA), USB is CPU-intensive protocol, so expect more nps dropdown.

Compare random vs sequential dropdown for Intel AHCI SATA vs USB 3.0 interfaces:

Intel RST SATA AHCI Drivers
Samsung 840 SSD 250GB
========================
Sequential Read : 514.179 MB/s
Sequential Write : 260.255 MB/s
Random Read 4KB (QD=1) : 24.252 MB/s [ 5921.0 IOPS]
Random Write 4KB (QD=1) : 45.642 MB/s [ 11143.1 IOPS]
Random Read 4KB (QD=32) : 254.315 MB/s [ 62088.6 IOPS]
Random Write 4KB (QD=32) : 179.794 MB/s [ 43895.1 IOPS]

Seagate USB 3.0 HDD
========================
Sequential Read : 61.168 MB/s
Sequential Write : 55.296 MB/s
Random Read 4KB (QD=1) : 0.362 MB/s [ 88.4 IOPS]
Random Write 4KB (QD=1) : 0.953 MB/s [ 232.6 IOPS]
Random Read 4KB (QD=32) : 0.439 MB/s [ 107.1 IOPS]
Random Write 4KB (QD=32) : 0.970 MB/s [ 236.9 IOPS]


do not compare absolute numbers (HDD's are different), but dropdown factor and IOPS.
For USB 3.0 random read speed (important for Syzygy probing) is 140x times slower than sequential read.
For SATA/AHCI it is only 2x slower.

IOPS are dramatically different: SATA is 580x times faster by IOPS

Another example SDCZ80-016G-X46 SanDisk USB 3.0 stick


random speed is 13x slower than sequential

i am not pretending to know of what i speak, but note that louis's link is to a product that markets itself as an external SSD, not a flash drive.

yanquis1972 wrote:i am not pretending to know of what i speak, but note that louis's link is to a product that markets itself as an external SSD, not a flash drive.

Yes, this is not a USB 3 flash drive. Wondering now about the effectiveness of the device for tablebase access.

Specs:

Controller: LSI SandForce 2281 Series with 7% Over Provisioning
Capacity: 120GB (128GB total flash memory with 8GB dedicated to real-time redundancy and error correction)*
Performance: up to 445MB/s read, up to 440MB/s write
Random 4K Performance: up to 39,000 IOPS
Interface Type: USB 3.0 (backward compatible to USB 2.0)
Dimensions: 3.66" x 0.94" x 0.47"
Weight: 2 ounces
Compatibility: Windows XP and higher / Mac OS X 10.4 and higher/Linux**
Warranty: 2 year

VisionTek mSATA mini USB 3.0 Bus-Powered SSD Enclosure


Benchmark Results: CrystalDiskMark showed that the Kingston 120GB SATA III 6.0Gb/s mSATA drive was getting sequential read and write speeds of 250 and 160 MB/s, which isn’t bad at all. When Joe reviewed this model mSATA SSD on a motherboard with an mSATA slot on it he was getting around 270MB/s read and 160MB/s write, so our numbers are just slightly lower than that. We expected somewhat lower performance due to the fact there is increased latency from the controller that coverts the mSATA drive over to USB 3.0.

Read more at http://www.legitreviews.com/visiontek-m ... FXsJ0rh.99


Results for product marketed SSD pretty much the same, as for SanDisk dongle.
I believe this is USB protocol design, not particular product issue.

Verbatim USB 3.0 External SSD 32 GB

blue - random read, red - random write

http://www.macworld.com/article/2039427 ... ally-.html