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hdfs block capacity chart

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Hi! I'd like to ask what is the actual meaning of the 'Block Capacity' chart for HDFS. The tsquery expression is known: 'SELECT block_capacity ...', but can't figure out where block_capacity is retrived from or how it is calculated.

 

The question arose after we have increased the 'Java Heap Size of NameNode in Bytes' for our Namenodes - we'd expect the block_capacity of the cluster would also grow, but actually it remains the same. Maybe we'd need to restart cluster to get this parameter updated?

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Thanks a million for your explanations. Indeed, the max block capacity cap was updated, but only after I changed Namenode's Java Heapsize for the second time. Anyway, now it shows higher cluster capacity, but actual value is a more than 2 times higher that what we expected assigning 1GB of RAM per 1 million of blocks. That's why I'd like to see how this value is actually calculated. Can't find it in CM.

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I am glad it's showing the increased values now. The following link might help, if not already referred to:

 

https://www.cloudera.com/documentation/enterprise/5-12-x/topics/admin_nn_memory_config.html

 

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Yep, we used it for estimating required memory. For now our block capacity is ok, thank you for help.