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List of Famous SMR Drives

The English-language original is published in the ixsystems forum and is hardly widely known to anyone who might run into a problem. Although the original is dated April 16, 2020, it also refers to later publications, that is, it was updated.

Hard drives that write data in overlapping,β€œTiled” paths * [under the stars - translator's note, see the end of the text] have a higher recording density than those that do not. For reasons of cost and capacity, manufacturers are increasingly switching to SMR, Shingled Magnetic Recording. SMR is a form of PMR (perpendicular magnetic recording). The tracks are perpendicular and superimposed on each other. In this table, CMR (Conventional Magnetic Recording) will mean β€œPMR without track overlay.”

SMR allows manufacturers to offer higher capacities without the need for a major change in underlying recording technology. Newer technologies, such as HAMR (Thermal Magnetic Recording), can be used with or without track overlay. The first such discs are expected in 2020, in any of the options.

SMR is well suited to provide high capacity at a low cost when the number of writes is small and reads are large.

SMR has worse sustained recording performance than CMR, which can cause serious problems during a reseller ** or other intensive recording operations, up to the failure of this reseller. In most cases, it is advisable to select a CMR drive. This post is an attempt to bring together well-known SMR disks and sources of this information.

There are three types of SMR:

  • , drive managed, DM-SMR, . , ZFS ZFS. : DM-SMR, , ( ), , ZFS . (h)
  • , Host Aware, HA-SMR, , ZFS*** SMR. , ZFS HA-SMR . HA-SMR DM-SMR , ZFS.
  • , Host Managed, HM-SMR, ZFS*** SMR.

I assume that ZFS does not currently handle HA-ZFS or HM-ZFS disks, as this would require rewriting block pointers. See page 24 (d), as well as (i) and (j).

Manufacturer and sizeModel No.TitleA typePrim
WD - 3.5 "Wd20efax2TB WD RedDM-SMR(1), EFRX is CMR
WD - 3.5 "WD30EFAX3TB WD RedDM-SMR(12) and inferred from (13), EFRX is CMR
WD - 3.5 "WD40EFAX4TB WD RedDM-SMR(1), EFRX is CMR
WD - 3.5 "Wd60efax6TB WD RedDM-SMR(1), EFRX is CMR
WD - 3.5 "WD20EZAZ2TB BlueDM-SMRInferred from (4), EZRZ is CMR
WD - 3.5 "WD30EZAZ3TB BlueDM-SMR?, EZRZ is CMR
WD - 3.5 "WD40EZAZ4TB BlueDM-SMR?, EZRZ is CMR
WD - 3.5 "WD60EZAZ6TB BlueDM-SMRInferred from (4), EZRZ is CMR
WD - 3.5 "Wd40emaz4TB ElementsDM-SMR(12)
WD - 3.5 "Wd60emaz6TB ElementsDM-SMR(12)
WD - 3.5 "WD60EDAZ6TB My BookDM-SMR(14)
Seagate - 3.5 "ST2000DM0052TB BarracudaDM-SMRInferred from (8)
Seagate - 3.5 "ST2000DM0082TB BarracudaDM-SMR(2)
Seagate - 3.5 "ST3000DM0073TB BarracudaDM-SMRInferred from (8)
Seagate - 3.5 "ST4000DM0044TB BarracudaDM-SMR(2)
Seagate - 3.5 "ST5000DM0035TB BarracudaDM-SMR2TB platter as per (15)
Seagate - 3.5 "ST6000DM0036TB BarracudaDM-SMRInferred from (8)
Seagate - 3.5 "ST8000DM0048TB BarracudaDM-SMR(2)
Seagate - 3.5 "ST5000DM0005TB DesktopDM-SMR(2)
Seagate - 3.5 "ST5000AS00115TB ArchiveDM-SMR(3)
Seagate - 3.5 "ST6000AS00026TB Archive v2DM-SMR(3)
Seagate - 3.5 "ST8000AS00028TB Archive v2HA-SMR(3) and (10)
Seagate β€” 3.5"ST8000AS00038TB Exos (Archive v3)DM-SMR(2)
Toshiba β€” 3.5"HDWD240UZSVA4TB P300 DesktopDM-SMR(11)
Toshiba β€” 3.5"HDWD260UZSVA6TB P300 DesktopDM-SMR(11)
Toshiba β€” 3.5"DT02ABA4004TB DT02(-V)DM-SMR(11)
Toshiba β€” 3.5"DT02ABA6006TB DT02(-V)DM-SMR(11)
HGST β€” 3.5"DC HC600 Series14TB, 15TB and 20TB UltrastarHM-SMR(9)
------------
Toshiba β€” 2.5"HDWL1101TB L200 SlimDM-SMR(11)
Toshiba β€” 2.5"HDWL1202TB L200DM-SMR(11), see also list at (18)
Toshiba β€” 2.5"MQ04ABF1001TB MQ04DM-SMR(11)
Toshiba β€” 2.5"MQ04ABD2002TB MQ04DM-SMR(11)
WD β€” 2.5"WD9000LPZX900GB BlueDM-SMR(16)
WD β€” 2.5"WD10SPZX1TB BlueDM-SMR(5), also as HGST Travelstar, see (20)
WD β€” 2.5"WD10SPWX1TB BlueDM-SMR(16)
WD β€” 2.5"WD20SPZX2TB BlueDM-SMR(6)
WD β€” 2.5"VariousNot For ResaleDM-SMRList at (17)
Seagate β€” 2.5"ST1000LM0481TB BarracudaDM-SMR(7), see also list at (19)
Seagate β€” 2.5"ST2000LM0152TB BarracudaDM-SMR(7), see also list at (19)
Seagate β€” 2.5"ST3000LM0243TB BarracudaDM-SMR(7), see also list at (19)
Seagate β€” 2.5"ST4000LM0244TB BarracudaDM-SMR(7), see also list at (19)
Seagate β€” 2.5"ST5000LM0005TB BarracudaDM-SMR(7), see also list at (19)


Additions from comments
1) WD - 2.5 "1TB Black WD10SPSX Source

2) About Seagate - it seems that there is a different design for the same model.
For an example, see the comments on ST3000DM001

[The following is a list of references and sources with links. Translate their names I see no reason]

(a) HA-SMR and HM-SMR in ZFS: 2014, Tim Feldman of Seagate, http://open-zfs.org/w/images/2/2a/Host-Aware_SMR-Tim_Feldman.pdf
( b) HA-SMR presentation, recording: 2014, Tim Feldman, https://www.youtube.com/watch?v=b1yqjV8qemU
Β© HA-SMR education: 2014, Mary Dunn and Tim Feldman of Seagate, https: // www .snia.org / sites / default / files / Dunn-Feldman_SNIA_Tutorial_Shingled_Magnetic_Recording-r7_Final.pdf
(d) ZFS on SMR: 2014, Robert Novak, https://storageconference.us/2014/Presentations/Novak.pdf
(e) HM-SMR paper: 2013, Albert Chen et al, WD: https: // www. snia.org/sites/default/files/SDC15_presentations/smr/AlbertChen_JimMalina_Host_Managed_SMR_revision5.pdf
(f) DM-SMR and CMR zones, resilvering woes: https://blocksandfiles.com/2020/04/15/shingled-drives non-shingled-zones-for-caching-writes /
(g) Code to make ext4 HA-SMR aware: 2015, Seagate, https://github.com/Seagate/SMR_FS-EXT4
(h) Performance and resilver results of using Seagata Archive v2 8TB on FreeNAS: https://www.ixsystems.com/community/threads/seagate-8tb-archive-drive-in-freenas.27740/page-2
(i) The intricacies of BPR: 2013, Matt Ahrens ,https://youtu.be/G2vIdPmsnTI?t=2675
(j) BPR is so complex no new features can be added afterwards: 2020, BSD Now podcast, from roughly 22:00, https://www.bsdnow.tv/ 340
(k) SMR presentation: 2015, Manfred Berger HGST, https://youtu.be/a2lnMxMUxyc
(l) OpenZFS Office Hour discussion on SMR: 2015, SMR, Resilvering, Possible Solutions at around 20, 31 and 46 mins respectively, https://youtu.be/mS4bfbEq46I?t=1220
(m) SAFS example file system for HA-SMR: 2015, Huewai R&D, https://www.snia.org/sites/default/files/SDC15_presentations/smr/ StephenMorgan-An_SMR-Aware_Append_Only-FiveSystem.pdf
(n) HiSMRFs research file system for SMR: 2014,https://www.researchgate.net/publication/271472461_HiSMRfs_A_high_performance_file_system_for_shingled_storage_array
(o) Poster for Zone-based Storage Tiering for HA-SMA: 2017, University of Minnesota, https://sc17.supercomputing_orgespc/ /post204s2-file2.pdf
(p) Manylogs concept, platters would need SMR and CMR sides: 2016, IEEE, https://ieeexplore.ieee.org/document/7897075
(q) Toshiba presentation on SMR technology: 2015, https: //www.toshiba.co.jp/tech/review/en/01_02/pdf/a08.pdf

Sources of claims that the drive uses SMR

(1) WD Red 2TB to 6TB are DM-SMR: https://blocksandfiles.com / 2020/04/14 / wd-red-nas-drives-shingled-magnetic-recording /
(2) Seagate drives that use DM-SMR: https://blocksandfiles.com/2020/04/15/seagate-2-4-and-8tb-barracuda-and-desktop-hdd-smr/
(3) Seagate data sheet for DM-SMR Archive drives: https://www.seagate.com/www-content/product-content/hdd-fam/seagate-archive-hdd/en-us/docs/archive-hdd-dS1834-3- 1411us.pdf
(4) WD data sheet for WD Blue, note 256MB cache suggesting DM-SMR: https://documents.westerndigital.com/content/dam/doc-library/en_us/assets/public/western-digital/product /internal-drives/wd-blue-hdd/data-sheet-wd-blue-pc-hard-drives-2879-771436.pdf
(5) User asserting 2.5 "WD Blue 1TB is SMR: https: //community.wd .com / t / smr-trim-on-a-wd10spzx-under-vista / 237101
(6) User asserting 2.5 "WD Blue 2TB is SMR:https://www.newegg.com/Product/SingleProductReview?reviewid=5188127
(7) Anandtech lists Seagate 2.5 "Barracuda as SMR: https://www.anandtech.com/show/10757/seagate-introduces-barracuda-25 -mobile-hard-drives-with-up-to-5-tb-capacity
(8) Seagate data sheet for Barracuda, note 256MB Multi-Tiered cache suggesting DM-SMR: https://www.seagate.com/www- content / datasheets / pdfs / 3-5-barracudaDS1900-11-1806US-en_US.pdf
(9) HGST Host-Managed SMR DataCenter drives: https://www.westerndigital.com/products/data-center-drives/ultrastar- dc-hc600-series-hdd
(10) Seagate datasheet for 8TB Archive v2 showing HA-SMR: https://www.seagate.com/www-content/product-content/hdd-fam/seagate-archive-hdd/en -us / docs / 100795782a.pdf
(11) Toshiba's list of DM-SMR drives: https://toshiba.semicon-storage.com/ap-en/company/news/news-topics/2020/04/storage-20200428-1.html
(12) WD platter sizes: https://rml527.blogspot.com/2010/10/hdd-platter-database-western-digital-35_9883.html |
(13) WD data sheet for WD Red, note 256MB cache suggesting DM-SMR: https://documents.westerndigital.com/content/dam/doc-library/en_us/assets/public/western-digital/product/internal- drives / wd-red-hdd / data-sheet-western-digital-wd-red-hdd-2879-800002.pdf
(14) WD platter sizes niche products: https://rml527.blogspot.com/2010/10/ hdd-platter-database-western-digital-35.html
(15) Seagate platter sizes:https://rml527.blogspot.com/2010/10/hdd-platter-database-seagate-35.html
(16) WD platter sizes 2.5 ": https://rml527.blogspot.com/2010/10/hdd- platter-database-western-digital-25.html
(17) WD platter sizes 2.5 niche products: https://rml527.blogspot.com/2010/10/hdd-platter-database-western-digital-25_2393.html
(18 ) Toshiba platter sizes 2.5 ": https://rml527.blogspot.com/2010/09/hdd-platter-database-toshiba-25.html
(19) Seagate platter sizes 2.5": https://rml527.blogspot.com /2010/09/hdd-platter-database-seagate-25.html
(20) HGST platter sizes 2.5 ": https://rml527.blogspot.com/2010/09/hdd-platter-database-hitachi-25.html

Translator notes

*)Brief information on what SMR

**) Resilver is - initially β€œsilvering again” when restoring a mirror. Currently, the term is much more actively used in the field of zfs and similar systems ... A good publicly available English definition of
Zpool Resilver is an operation to restore parity in a pool or due to a damaged device (for example, a disk may temporarily fall out and you need to β€œcatch up”), either due to a recently replaced device.
I will use the transliteration β€œreseller”.

***) SMR in general and, in particular, HA-SMR, are developed without any regard to ZFS. Therefore, IMHO the definition of the author should be considered as partial, referring only to ZFS - which does not, however, change the essence. Let me remind you that HM-SMR and HA-SMR disks are already available on the market (and are listed in the table in this post).

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