Part 1 – Summary. How to find the IBM Looking at IBM Spect Sequential Processing When it comes to sequential reads and writes, here you can get the benefits of both capacity and bandwidth. What striping is happening where?

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Since arrays can be accessed through both nodes in the V system, 4 is enough, on each node, one array will be assigned and processed through one core.

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To write a ful stride, we need to write to all data disks. How to find the IBM That means you need at least 4 arrays per V to get maximal CPU core performance. In this case, 8 data disks, so 8x kb 2MB.

An array has a defined strip size. You lose the parity disk’s worth of capacity with parity data.

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What striping is happening where? There are so many svcc that contribute to getting the best performance out of a storage system, that it really does depend on what you are trying to achieve.

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This is commonly referred to as “full stride writes” or “full strip writes” – essentially you are writing all new data across all disk that make up the array, and in memory, calculating the new parity data.

When a RAID-5 array has to write to a strip, it needs to read the existing strip, read the existing parity strip, update the existing strip read modify, write and then svvc the new parity.

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Do you need the most MB or GB per second? In Part 3, I will discuss storage pool configurations, mdisk groups in old SVC parlance And finally in Part 4, I will discuss volume vdisk and host configurations. Lets say the strip is kb.

Part 1 – Summary. With V, always configure at least 4 arrays, and if possible, multiples of 4.

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I was once creditied in an IBM Redbook, with the comment: Is the workload random or sequential? Is the host optimally configured for the storage system?

Looking at IBM Spect Any questions, feel free to ask. Optimal configurations require at least 4 arrays, to ensure maximal core usage.


Within the SVC softare that runs on the V, we have worked for many years over 12 now on making the code path and per core processing as consistent as possible. Find the duplicate idea: Now we only have to use 9x kb writes, and no reads. Thats because when it comes to all things related to storage performance, more often than not, “it depends”. Type in a Name: Provide a reason for quarantining this blog entry optional: Here your reads will come from just one disk in the array.

Sequential Processing When it comes to sequential reads and writes, here you can get the benefits sfd both capacity and bandwidth. Previous Entry Main Next Entry. If the host then issues a single 2MB write, we can write across all 8 strips, in memory calculate the parity and write that too.