The following is the fifth in a series of blog posts from members of the Avid storage team discussing how ISIS shared storage overcomes challenges in an era where media is created and consumed everywhere.
My dog Lucy is now 9 years old, every time I come home she comes running to the door wagging her tail, ready to go out or just hang out with her human family. Even when we’re not doing much, she does her rounds to check on all of us to make sure we are OK. Over the years Lucy has become a trusted, reliable and dependable part of the family. Avid ISIS video editing shared storage is just like a loyal dog, it is completely dependable, predictable and there when you need it. Today’s post production workflows require more media to be readily available and shortened delivery deadlines demand faster turn-around and improved operational efficiency.
Avid ISIS shared storage raises dependability to a higher level.
The ISIS family of shared storage solutions provides many of the availability features you might not find on other alternatives – we have redundant power and cooling and Mirror or RAID protection for media and project files. On top of that, ISIS raises dependability to a higher level.
ISIS provides dual system drives, this gives protection against a boot drive failure meaning ISIS will be ready and waiting to go whenever you need it. ISIS also leverages the redundant boot drives to store two copies of the ISIS File System (ISIS FS) meta data. This meta data is critical, it enables the translation between the directory structure and filename presented to the client machine’s operating system and the media chunk layout across the ISIS servers and drives. The primary copy of meta-data is held in system memory to deliver high performance and frequent backups are written to the mirrored system drives. This gives two backup copies in case of system restart or system drive failures. ISIS products offer Redundant or Resilient System Director configurations to further increase the media availability by syncing the metadata to a second system director.
Performance is the same as when it was first installed, even after many years of use.
Another level that contributes greatly to the dependability of ISIS is the upfront qualification of all components that make up an ISIS system. One very important aspect is Hard Disk Drive (HDD) performance characteristics and error handling. We put drives through a rigorous qualification process that tests performance at the drive level across all parts of the disk drive platter. Some vendors only quote performance from the optimal part of the disk which means performance degrades the more the system is used. ISIS is designed to be consistent; the media is laid out across the disk drives so that the performance is the same as when it was first installed, even after many years of use. We impose additional acceptance testing criteria on the HDD manufactures that weeds out drives that might meet their standards for general use, but do not meets Avid’s higher standards for use in post production workflows. Thus storage devices from other vendors are potentially using drives rejected by the ISIS qualification process.
Importantly we also optimize the error response at the drive level. Typical drive behavior is to retry a read or write operation if the original request is unsuccessful. This may be a reasonable approach for clients (PC / Mac workstations) where the required data is stored on a single disk. However, in ISIS media is either mirrored or RAID protected meaning we have other places to find the media or a mechanism to recreate it from the RAID parity, to address the need to deliver data to editing applications in real time to deliver a great playback experience. The drives in ISIS have optimized firmware to limit the time spent recovering from an initial read failure and to quickly respond with an error allowing ISIS FS to access the mirror or parity to meet the delivery requirement.
On top of all of this ISIS FS has a patented client “Due Time” mechanism to explicitly request frames within a delivery deadline. This allows the ISIS storage to optimize the scheduling of I/O (input / output) requests to disks so that the deadlines of multiple editors can be met. How this is done will be the subject of another blog.
As you can see, ISIS video editing shared storage has a number of unique approaches to make it the most dependable and predictable ‘old friend’ in the media world, it is always there when you need it and its always up to the task. Talk to your reseller or Avid representative about adding the dependability of ISIS to your workflow.