Fujitsu ETERNUS DX500 S3/DX600 S3, Руководство по конструкции

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Policies for Estimating Cache Memory
When installing cache memory, select the cache memory capacity according to the physical drive capacity and
the operation contents (the method to access data).
Since the total capacity of data that is to be handled increases in proportion to the total capacity of the drives
that are accessed, more cache memory needs to be installed when additional capacity for drives is installed. If
the cache memory capacity is insufficient, data is read from the drives and performance is reduced because data
cannot be read from the cache memory (cache miss).
The following guidelines show the basic capacity of the cache memory according to the drive capacity (*1) and
the recommended cache memory capacity when using the functions.
*1: Use the total capacity of the drives that are accessed during operation for the drive capacity.
When work is separated by time, such as between daytime and nighttime, cache memory capacity can be
calculated by using the task that requires the most capacity from the drives that are accessed.
It can also be calculated by using the drive capacity for tasks that place a priority on response time.
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Basic Capacity of the Cache Memory
The required capacity for cache memory is calculated according to the drive capacity of the access target.
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ETERNUS DX500 S4
Table 51 Estimated Cache Memory Capacity (ETERNUS DX500 S4)
Drive capacity
Cache memory capacity (per storage
system)
Cache memory capacity (per CM)
Up to 5,120GB 16GB 8GB
5,120GB or more 32GB 16GB
15,360GB or more 64GB 32GB
32,000GB or more 128GB 64GB
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ETERNUS DX600 S4
Table 52 Estimated Cache Memory Capacity (ETERNUS DX600 S4)
Drive capacity
Cache memory capacity (per storage
system)
Cache memory capacity (per CM)
Up to 7,680GB 32GB 16GB
7,680GB or more 64GB 32GB
17,920GB or more 128GB 64GB
47,360GB or more 256GB 128GB
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ETERNUS DX500 S3
Table 53 Estimated Cache Memory Capacity (ETERNUS DX500 S3)
Drive capacity
Cache memory capacity (per storage
system)
Cache memory capacity (per CM)
Up to 12,800GB 16GB 8GB
12,800GB or more 32GB 16GB
20,480GB or more 64GB 32GB
5. Hardware Configurations
Optional Product Installation Conditions
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FUJITSU Storage ETERNUS DX500 S4/DX600 S4, ETERNUS DX500 S3/DX600 S3 Hybrid Storage Systems Design Guide (Basic)
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