No, the STC 4305 was compatible with a disk drive, not with a drum. By the time the 4305 came along, nobody was buying drums.
-- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 ________________________________________ From: IBM Mainframe Discussion List <IBM-MAIN@listserv.ua.edu> on behalf of Allan Staller <allan.stal...@hcl.com> Sent: Wednesday, December 20, 2017 9:16 AM To: IBM-MAIN@listserv.ua.edu Subject: Re: Can anyone remember "drum" storage? "pseudo-drum" - STK4305. I remember it well <sigh> -----Original Message----- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf Of Joel C. Ewing Sent: Wednesday, December 20, 2017 8:15 AM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Can anyone remember "drum" storage? I don't think so. Says each R/W head accesses same disk blocks, and there would be zilch improvement in speed if they were simply seen by OS as two independent disks. By electronically selecting which of the two heads to use to read the track based on which sees the start of the desired block first, you cut the rotational latency time in half. With a single R/W head the only way to get the same reduction in latency delay would be to double the rotational speed of the platter, which might cause greater problems. J C Ewing On 12/20/2017 07:18 AM, Tony Thigpen wrote: > From reading the description, it really just appears to the OS as two > drives in one housing. > > Tony Thigpen > > John McKown wrote on 12/20/2017 08:08 AM: >> It's not really a drum, but it is getting closer. Of course, for true >> speed, one should go SSD. >> >> https://secure-web.cisco.com/1p8mYoOk7OUx1hqtHvkoSmFVBY0PdswHDgZYedgomJZdjTVyBLHFXGjrTvK4ueCAi7MQjDovlctC_dEtCtwD7AE7CN2vq_T1iy66t53e2QJiehT6FyT68EwaEhns5IVW1adAcE9afdIy-ctZI4hLmN5jHTSEoYCzki0SiO7FDr5FKvLbf66nWxBODRDu5A2e7Ro2miW-0dR4pIdHsLxrIK_vJD03qDutulu_P9S1WbUvJeaC81ZKDGMn58W6gmnAd6UF4p44e2dDThjRdbGqS4cnvMwWLUWzpe8u50Nj50ihst1t6SO03FWnPl77wy0C7uvWwFa0xo94jgC8t9y0KNDP4Jdj9oELxJhRqUdjkLg_UNoIjwUqEMFoTruRcoIIWu4c9AyAkq23ydRYIxee43KdZj3VGuPvdmYmHUsu4nYMJXGtnHdHC11A5jl4iSm1r/https%3A%2F%2Fapac01.safelinks.protection.outlook.com%2F%3Furl%3Dhttp%253A%252F%252Fwww >> .theregister.co.uk%2F2017%2F12%2F19%2Fseagate_disk_drive_multi_actuat >> or%2F&data=02%7C01%7Callan.staller%40HCL.COM%7C1e585afeeaf14753335808 >> d547b42536%7C189de737c93a4f5a8b686f4ca9941912%7C0%7C0%7C6364937614319 >> 95373&sdata=7BNHk4Ci%2Fq8zLD%2BgBDHrtFQOcgyBXiT1kUg1nK3fD6I%3D&reserv >> ed=0 >> >> >> [quote] >> >> Seagate is increasing IO performance in disk drives by separating >> read-write heads into two separate sets which can operate >> independently and in parallel. >> >> The heads are positioned at one end of actuator arms which rotate >> around a post at their other end to move the heads across the platter >> surfaces. >> Thus, with an eight-platter drive, each read-write head is positioned >> above the same cylindrical track on each platter and reads or writes >> to and from the same disk blocks on each platter's surface. >> >> [\quote] >> >> > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, send > email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN > -- Joel C. Ewing, Bentonville, AR jcew...@acm.org ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN ::DISCLAIMER:: ---------------------------------------------------------------------------------------------------------------------------------------------------- The contents of this e-mail and any attachment(s) are confidential and intended for the named recipient(s) only. E-mail transmission is not guaranteed to be secure or error-free as information could be intercepted, corrupted, lost, destroyed, arrive late or incomplete, or may contain viruses in transmission. The e mail and its contents (with or without referred errors) shall therefore not attach any liability on the originator or HCL or its affiliates. Views or opinions, if any, presented in this email are solely those of the author and may not necessarily reflect the views or opinions of HCL or its affiliates. Any form of reproduction, dissemination, copying, disclosure, modification, distribution and / or publication of this message without the prior written consent of authorized representative of HCL is strictly prohibited. If you have received this email in error please delete it and notify the sender immediately. Before opening any email and/or attachments, please check them for viruses and other defects. ---------------------------------------------------------------------------------------------------------------------------------------------------- ::DISCLAIMER:: ---------------------------------------------------------------------------------------------------------------------------------------------------- The contents of this e-mail and any attachment(s) are confidential and intended for the named recipient(s) only. E-mail transmission is not guaranteed to be secure or error-free as information could be intercepted, corrupted, lost, destroyed, arrive late or incomplete, or may contain viruses in transmission. The e mail and its contents (with or without referred errors) shall therefore not attach any liability on the originator or HCL or its affiliates. Views or opinions, if any, presented in this email are solely those of the author and may not necessarily reflect the views or opinions of HCL or its affiliates. Any form of reproduction, dissemination, copying, disclosure, modification, distribution and / or publication of this message without the prior written consent of authorized representative of HCL is strictly prohibited. If you have received this email in error please delete it and notify the sender immediately. Before opening any email and/or attachments, please check them for viruses and other defects. ---------------------------------------------------------------------------------------------------------------------------------------------------- ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
