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xerces8's Achievements


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  1. It is a common problem with many USB enclosures. Do other hard drives return more information in the same enclosure? What software did you try? CrystalDiskInfo for example returns SMART data when HDTune does not. (yes, HDTune is old, just an example)
  2. Those sectors were corrupted. Now they are overwritten with error-free content. A quite normal scenario.
  3. Linear reads on SMR are the same as on non-SMR drives. The biggest difference is in the random write test (10 times faster than non-SMR due to the track cache). And hammering it with a _lot_ of read/write requests (similar results as non-SMR except for the occasional long delay). Not exactly a one-click thing, but enough to get a few good hints.
  4. Well, you could test them, to see if they are SMR or not.
  5. I got a WD My Book 8 TB (WDBBGB0080HBK-EESN) and after some testing it looks like a non-SMR drive. See CDM screenshot attached (the disk was 99.999% full, to make it "sweat", the test with 0% full is almost the same except the SEQ values being 199MB/s). Also test with FIO as per this post suggests it is not SMR. The summary: TEST: (groupid=0, jobs=1): err= 0: pid=4768: Tue Sep 10 22:24:49 2019 write: IOPS=7, BW=73.2MiB/s (76.8MB/s)(85.8GiB/1200024msec) slat (usec): min=353, max=4294.0k, avg=2579.76, stdev=71064.79 clat (usec): min=2, max=9319.4k, avg=69451.95, stdev=100307.35 lat (msec): min=35, max=402895, avg=136.54, stdev=4401.42 clat percentiles (msec): | 1.00th=[ 41], 5.00th=[ 47], 10.00th=[ 51], 20.00th=[ 57], | 30.00th=[ 61], 40.00th=[ 64], 50.00th=[ 67], 60.00th=[ 70], | 70.00th=[ 74], 80.00th=[ 80], 90.00th=[ 87], 95.00th=[ 93], | 99.00th=[ 114], 99.50th=[ 188], 99.90th=[ 234], 99.95th=[ 239], | 99.99th=[ 9329] bw ( KiB/s): min=19922, max=183585, per=100.00%, avg=144614.45, stdev=17834.58, samples=1226 iops : min= 1, max= 17, avg=13.38, stdev= 1.78, samples=1226 lat (usec) : 4=0.02%, 20=0.02%, 50=0.05%, 100=0.01% lat (msec) : 50=9.84%, 100=87.85%, 250=2.17%, 500=0.02% cpu : usr=0.33%, sys=0.42%, ctx=0, majf=0, minf=0 IO depths : 1=100.0%, 2=0.0%, 4=0.0%, 8=0.0%, 16=0.0%, 32=0.0%, >=64=0.0% submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0% complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0% issued rwts: total=0,8788,0,0 short=0,0,0,0 dropped=0,0,0,0 latency : target=0, window=0, percentile=100.00%, depth=1 Run status group 0 (all jobs): WRITE: bw=73.2MiB/s (76.8MB/s), 73.2MiB/s-73.2MiB/s (76.8MB/s-76.8MB/s), io=85.8GiB (92.1GB), run=1200024-1200024msec
  6. Recently I bought (see other topic) an external USB drive from WD, hoping it would be not SMR, but it turned out to be such. Are there any non-SMR USB drives on the market at the lower price range? I'm loking at sizes of 5-6 TB.
  7. After filling it to about half and rerunning CDM, I got the typical values for 4K: read about 0.5 MB/s, write 6 MB/s
  8. CrystalDiskInfo says: Enclosure : WD My Book 25EE USB Device (V=1058, P=25EE, sa1) - Model : WDC WD60EDAZ-11BMZB0 Firmware : 80.00A80MZB0
  9. I purchased a WD 6 TB My Book Desktop Hard Drive - Black WDBBGB0060HBK (from Amazon, see link) and after running CDM is seems like it is a SMR drive: Did WD start selling SMR units? Or am I misinterpreting the results? Is there a reliable test to determine if a unit is SMR or not?
  10. Hi! Is there more info on what exactly is TGMR? I have a 8TB Seagate Desktop drive (CystalDiskInfo says it is a ST8000DM004-2CX188, haven't shucked it yet). The interesting thing is, CDM shows normal (as in "not SMR") values for 4K writing (same as for reading, about 1 MB/s), unlike about 10 MB/s, like for example my other 5TB SMR drive. Regards, David