Tag - disk seek

Making “Insert Ignore” Fast, by Avoiding Disk Seeks

In my post from three weeks ago, I explained why the semantics of normal ad-hoc insertions with a primary key are expensive because they require disk seeks on large data sets. Towards the end of the post, I claimed that it would be better to use “replace into” or “insert ignore” over normal inserts, […]

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Making “Replace Into” Fast, by Avoiding Disk Seeks

In this post two weeks ago, I explained why the semantics of normal ad-hoc insertions with a primary key are expensive because they require disk seeks on large data sets. Towards the end of the post, I claimed that it would be better to use “replace into” or “insert ignore” over normal inserts, because […]

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Making Updates Fast, by Avoiding Disk Seeks

The analysis that shows how to make deletions really fast by using clustering keys and TokuDB’s fractal tree based engine also applies to make updates really fast. (I left it out of the last post to keep the story simple). As a quick example, let’s look at the following statement:

Shell

update foo set price=price+1 where […]

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Disk seeks are evil, so let’s avoid them, pt. 4

Continuing in the theme from previous posts, I’d like to examine another case where we can eliminate all disk seeks from a MySQL operation and therefore get two orders-of-magnitude speedup. The general outline of these posts is:

B-trees do insertion disk seeks. While they’re at it, they piggyback some other work on the […]

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Making Deletions Fast, by Avoiding Disk Seeks

In my last post, I discussed how fractal tree data structures can be up to two orders of magnitude faster on deletions over B-trees. I focused on the deletions where the row entry is known (the storage engine API handler::delete_row), but I did not fully analyze how MySQL delete statements can be fast. In […]

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