Access times for Windows Azure storage tables

Question

My company is interested in using the azure storage tables. They have asked me to look into access times but so far I have not found any information on this. I have a few questions that perhaps some person here could help answer.

• Any information / links or anything on the read / write access times of azure table storage
• If I use a partition key and row key for direct access does read time increase with number of fields
• Is anyone aware of future plans for azure storage such as decrease in price, increase in access speed, ability to index or increase in size of storage per row
• Storage is I understand 1MByte / row. Does this include space for the field names. I assume it does
• Is there any way to determine how much space is used for a row in Azure storage. Any API for this.

Hope someone can help answer even one or two of these questions.

PLEASE note this question only applies to TABLE STORAGE.

Thanks

Answer 1

Microsoft has a blog post about scalability targets.

For actual storage per row, here's an excerpt from that post:

Entity (Row) – Entities (an entity is analogous to a "row") are the basic data items stored in a table. An entity contains a set of properties. Each table has two properties, “PartitionKey and RowKey”, which form the unique key for the entity. An entity can hold up to 255 properties Combined size of all of the properties in an entity cannot exceed 1MB. This size includes the size of the property names as well as the size of the property values or their types.

You should see performance around 500 transactions per second, on a given partition.

I know of no plans to reduce storage cost. It's currently at $0.15 / GB / month.

You can optimize table storage write speed by combining writes within a single partition - this is an entity group transaction. See here for more detail.

Answer 2

To add to David's answer. The Microsoft Extreme Computing Group have a pretty comprehensive series of performance benchmarks on all things Azure, including Azure tables.

From the above benchmarks (under read latency):

Entity size does not significantly affect the latencies

So I wouldn't be overly concerned about adding more properties.

Secondary indexes on Azure Tables have come up as a requested feature since it was first release and at one point it was even talked about as if it was going to be in an upcoming release. MS has since fallen very quiet about it. I understand that MS are working on it (or at the very least thinking very hard about it), but there is no time frame for when/if it will be released.