{"id":208,"date":"2010-12-05T14:55:02","date_gmt":"2010-12-05T21:55:02","guid":{"rendered":"http:\/\/www.hd4pc.com\/techblog\/?p=208"},"modified":"2010-12-05T14:55:32","modified_gmt":"2010-12-05T21:55:32","slug":"post-production-media-storage-and-drive-arrays","status":"publish","type":"post","link":"https:\/\/www.hd4pc.com\/techblog\/2010\/12\/05\/post-production-media-storage-and-drive-arrays\/","title":{"rendered":"Post Production Media Storage and Drive Arrays"},"content":{"rendered":"

After my last article explained why USB3<\/a> is not ready to be used as the interface for primary media editing drives, this has led to the question of: what interface should be used for attaching media arrays to editing workstations for maximum system performance?\u00c2\u00a0 Even more so than with basic external hard drives, there are a number of competing options, none of which have emerged as clearly superior.\u00c2\u00a0 At this point the answer really varies a lot depending on your needs and budget. \u00c2\u00a0It has been three years since my last article on the subject, so the market has changed considerably since then. \u00c2\u00a0The primary options as I see it, are eSATA<\/a>, SAS<\/a>,\u00c2\u00a0external PCIe<\/a>, and Fibre Channel<\/a>.\u00c2\u00a0 While older parallel SCSI<\/a> based devices are technically still available, the interface has no real advantages over even eSATA, let alone the more expensive options.
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\neSATA<\/a> is of course based on the popular SATA interface, and connects an array of drives to a system in their native interface.\u00c2\u00a0\u00c2\u00a0Most RAID<\/a> redundancy is usually accomplished at the controller level, with a PCI expansion card <\/a>inside the workstation. \u00c2\u00a0Some arrays are capable of creating integrated RAID <\/a>sets, which are presented to the host system as single large volumes.\u00c2\u00a0 One of the advantages of this approach is that the array can be connected to other systems without needing to match the internal RAID controller card for the array to function properly.\u00c2\u00a0 While a single 300MB\/s SATA channel will be sufficient for simpler compressed HD workflows on a budget, most professional arrays for high end editing systems will need more bandwidth than that, so most large eSATA arrays connect to the workstation with 1 or 2 four channel<\/a> cables<\/a>,\u00c2\u00a0using a variety of different physical interfaces depending on the vendor.<\/p>\n

External SAS<\/a> connected arrays<\/a> function in much the same way as SATA based ones, but with a few advantages, that usually come at a significantly higher cost.\u00c2\u00a0 SAS is a full duplex interface, and the command set is based on SCSI instead of IDE, allowing higher performance and throughput.\u00c2\u00a0 More expensive SAS arrays also support multipath signaling, for greater redundancy in the supporting electronics.\u00c2\u00a0(As opposed to the redundancy provided at the disk level by RAID configurations) \u00c2\u00a0SAS also supports much longer cable<\/a> lengths, up to\u00c2\u00a010 meters or\u00c2\u00a030 feet.\u00c2\u00a0 This\u00c2\u00a0can be advantagious for quiet video editing rooms, since the disk array, which is usually the loudest part of the system, can be located farther away from the users.<\/p>\n

A number of vendors have now begun offering external arrays that interface with the host workstation via a direct extension of the PCIe bus<\/a>. \u00c2\u00a0This allows all of the RAID functionality to be contained within the array, and gives full speed access to the data as if it was contained within the machine.\u00c2\u00a0 Among the advantages of removing the RAID functionality from an internal\u00c2\u00a0add-on card, are that it can be attached to a laptop via an ExpressCard, which uses the same signaling protocol as PCIe, and that with addition of a few cheap pass-thru cards<\/a>, an array can easily be moved between systems.\u00c2\u00a0 This is definitely not a hot swappable solution, since it accesses the PCIe bus directly, which is initialized at bootup on most systems.\u00c2\u00a0 But if your main edit system has a total OS meltdown at a critical point in your project, it should be much easier to access your data from a different system than if you needed to reinstall the PCI SATA RAID card somewhere else, and allow you use your laptop as a backup edit system in certain instances.<\/p>\n

Fibre Channel is by far the most expensive option.\u00c2\u00a0 Every part of the system is more expensive, the PCIe HBA cards<\/a>, the fiber cables<\/a>, and the\u00c2\u00a0disk array controllers<\/a>.\u00c2\u00a0 On the otherhand, Fibre Channel offers capabilities that none of the other storage options really do.\u00c2\u00a0 It is a hot swappable interface, running on fiber cables that can\u00c2\u00a0extend access\u00c2\u00a0thousands of feet if desired, and can easily be networked and shared.\u00c2\u00a0 Devices can be connected directly together, shared in an Arbitrated Loop<\/a>, or all\u00c2\u00a0attached to a central fibre switch for simplified management.\u00c2\u00a0 It is an efficient and low latency interface, and is available in speeds of 1,2,4, or 8Gb per second, and multiple channels can be combined for higher performance.\u00c2\u00a0 Higher speed devices are usually backwards compatible with older hardware, similar to the way ethernet <\/a>works,\u00c2\u00a0allowing you\u00c2\u00a0to upgrade your storage network one piece at a time.<\/p>\n

Choosing the right storage solution depends on your immediate media needs, your available budget, and the direction you anticipate growing in the future. SATA based solutions offer all of the speed you could need if scaled large enough. \u00c2\u00a0SAS can offer similar performance in a smaller package, but at a higher cost.\u00c2\u00a0 Sharing data beyond gigabit network speeds\u00c2\u00a0requires a storage system that can interface with multiple computers, but that comes at a significantly increased initial cost. \u00c2\u00a0Investing in Fibre Channel\u00c2\u00a0storage is usually only worth the expense if you anticipate the need to share your data on a SAN, either immediately or at some point in the future.\u00c2\u00a0 I will examine a few popular shared SAN<\/a> options in my next post.<\/p>\n","protected":false},"excerpt":{"rendered":"

After my last article explained why USB3 is not ready to be used as the interface for primary media editing drives, this has led to the question of: what interface should be used for attaching media arrays to editing workstations for maximum system performance?\u00c2\u00a0 Even more so than with basic external hard drives, there are […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8,17],"tags":[24,34,35,33,32],"_links":{"self":[{"href":"https:\/\/www.hd4pc.com\/techblog\/wp-json\/wp\/v2\/posts\/208"}],"collection":[{"href":"https:\/\/www.hd4pc.com\/techblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.hd4pc.com\/techblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.hd4pc.com\/techblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.hd4pc.com\/techblog\/wp-json\/wp\/v2\/comments?post=208"}],"version-history":[{"count":7,"href":"https:\/\/www.hd4pc.com\/techblog\/wp-json\/wp\/v2\/posts\/208\/revisions"}],"predecessor-version":[{"id":215,"href":"https:\/\/www.hd4pc.com\/techblog\/wp-json\/wp\/v2\/posts\/208\/revisions\/215"}],"wp:attachment":[{"href":"https:\/\/www.hd4pc.com\/techblog\/wp-json\/wp\/v2\/media?parent=208"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.hd4pc.com\/techblog\/wp-json\/wp\/v2\/categories?post=208"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.hd4pc.com\/techblog\/wp-json\/wp\/v2\/tags?post=208"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}