Re: Pluggable throttling of read and write queries

2017-02-20 Thread Jeff Jirsa
On 2017-02-20 22:47 (-0800), Benjamin Roth wrote: > Thanks. > > Depending on the whole infrastructure and business requirements, isn't it > easier to implement throttling at the client side? > I did this once to throttle bulk inserts to migrate whole CFs from other >

Re: Pluggable throttling of read and write queries

2017-02-20 Thread Benjamin Roth
Thanks. Depending on the whole infrastructure and business requirements, isn't it easier to implement throttling at the client side? I did this once to throttle bulk inserts to migrate whole CFs from other DBs. 2017-02-21 7:43 GMT+01:00 Jeff Jirsa : > > > On 2017-02-20 21:35

Re: Pluggable throttling of read and write queries

2017-02-20 Thread Jeff Jirsa
On 2017-02-20 21:35 (-0800), Benjamin Roth wrote: > Stupid question: > Why do you rate limit a database, especially writes. Wouldn't that cause a > lot of new issues like back pressure on the rest of your system or timeouts > in case of blocking requests? > Also rate

Re: Pluggable throttling of read and write queries

2017-02-20 Thread Jeff Jirsa
On 2017-02-17 18:12 (-0800), Abhishek Verma wrote: > > > Is there a way to throttle read and write queries in Cassandra currently? > If not, what would be the right place in the code to implement a pluggable > interface for doing it. I have briefly considered using triggers,

Re: Does C* coordinator writes to replicas in same order or different order?

2017-02-20 Thread Dor Laor
+ The C* coordinator send async write requests to the replicas. This is very important since it allows it to return a low latency reply to the client once the CL is reached. You wouldn't want to serialize the replicas one after the other. + The client <-> server sync/async isn't related

Pluggable throttling of read and write queries

2017-02-20 Thread Edward Capriolo
Older versions had a request scheduler api. On Monday, February 20, 2017, Ben Slater > wrote: > We’ve actually had several customers where we’ve done the opposite - split > large clusters apart to separate

Does C* coordinator writes to replicas in same order or different order?

2017-02-20 Thread Kant Kodali
Hi, when C* coordinator writes to replicas does it write it in same order or different order? other words, Does the replication happen synchronously or asynchrnoulsy ? Also does this depend sync or async client? What happens in the case of concurrent writes to a coordinator ? Thanks, kant

Are Cassandra Triggers Thread Safe? ("Tough questions perhaps!")

2017-02-20 Thread Kant Kodali
Hi, 1. Are Cassandra Triggers Thread Safe? what happens if two writes invoke the trigger where the trigger is trying to modify same row in a partition? 2. Had anyone used it successfully on production? If so, any issues? (I am using the latest version of C* 3.10) 3. I have partitions that are

Re: Pluggable throttling of read and write queries

2017-02-20 Thread Ben Slater
We’ve actually had several customers where we’ve done the opposite - split large clusters apart to separate uses cases. We found that this allowed us to better align hardware with use case requirements (for example using AWS c3.2xlarge for very hot data at low latency, m4.xlarge for more general

Re: [VOTE] Release Apache Cassandra 2.2.9

2017-02-20 Thread Tommy Stendahl
+1 (non-binding) On 2017-02-16 02:16, Michael Shuler wrote: I propose the following artifacts for release as 2.2.9. sha1: 70a08f1c35091a36f7d9cc4816259210c2185267 Git: http://git-wip-us.apache.org/repos/asf?p=cassandra.git;a=shortlog;h=refs/tags/2.2.9-tentative Artifacts:

Re: Pluggable throttling of read and write queries

2017-02-20 Thread Oleksandr Shulgin
On Sat, Feb 18, 2017 at 3:12 AM, Abhishek Verma wrote: > Cassandra is being used on a large scale at Uber. We usually create > dedicated clusters for each of our internal use cases, however that is > difficult to scale and manage. > > We are investigating the approach of using a