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From lars hofhansl <lhofha...@yahoo.com>
Subject Re: How many tablets can bigtable store?
Date Sun, 05 Feb 2012 00:16:46 GMT
```Hi Roger,

I think the math goes like this:
If the root tablet is held in 128mb memory and each entry is 1k that means that there can
be 128mb/1k = 131072 = 2^17 meta tablets.
By the same logic each meta tablet can hold 2^17 entries, so you get 2^17 * 2^17 = 2^34 tablets
in total.

-- Lars

________________________________
From: Roger <rogerdai@qq.com>
To: user <user@hbase.apache.org>
Sent: Saturday, February 4, 2012 5:20 AM
Subject: How many tablets can bigtable store?

Hi everyone,
I was reading bigtable paper these days.
And from the paper, I have a little question.

"Each METADATA row stores approximately 1KB of data in memory. With a modest limit of 128
MB
METADATA tablets, our three-level location scheme is sufficient to address 2^34 tablets."

I am confusing because 2^10 * 2^7 = 2^17
How could it store 2^34 tablets?

------------------
Regards,
Q
```
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