# Linear scalability test
**URL:** https://forum.yugabyte.com/t/linear-scalability-test/526
**Category:** General
**Created:** [October 5, 2019, 4:06pm UTC](https://forum.yugabyte.com/t/linear-scalability-test/526 "2019-10-05T16:06:39Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@ivan\_s](https://forum.yugabyte.com/u/ivan_s)
#### Post date: [October 5, 2019, 4:06pm UTC](https://forum.yugabyte.com/t/linear-scalability-test/526/1 "2019-10-05T16:06:39Z")
Hello.
I used instructions [Horizontal scalability | YugabyteDB Docs](https://docs.yugabyte.com/latest/explore/linear-scalability/#docker)
1. I ran ./yb-docker-ctl create --rf 3 --num\_shards\_per\_tserver 4
2. I ran `docker run --name yb-sample-apps --hostname yb-sample-apps --net yb-net yugabytedb/yb-sample-apps --workload SqlInserts \ --nodes yb-tserver-n1:5433 \ --num_threads_write 1 \ --num_threads_read 4`
3. Everything was fine.
4. I added the node ./yb-docker-ctl add\_node --num\_shards\_per\_tserver 4
5. Everything worked, but requests were distributed unevenly: [Screenshot by Lightshot](https://prnt.sc/pf9mzx) (n4 and n1 servers). **Why?**
6. I deleted the node ./yb-docker-ctl remove\_node 4
7. Reading and writing fell to zero [488127 [Thread-1] INFO com.yugabyte.sample.common.metrics.MetricsTracker - Read - Pastebin.com](https://pastebin.com/j5dD7gbX)
**Why?**
8. I decided to restart yb-sample-apps and got this error [docker run --name yb-sample-apps --hostname yb-sample-apps --net yb-net yugabyte - Pastebin.com](https://pastebin.com/VbVsAtkP) .
**Why?**
9. And when I created the node, I didn’t get yb-master-n4. I only got yb-tserver-n4. Is it right?
Maybe I didn’t understand how it works. Help please.
p.s. I use Docker
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### Author:  [@dorian\_yugabyte](https://forum.yugabyte.com/u/dorian_yugabyte)
#### Post date: [October 7, 2019, 8:15am UTC](https://forum.yugabyte.com/t/linear-scalability-test/526/2 "2019-10-07T08:15:01Z")
@ivan_s
Can you paste the error/info logs of all the tservers/masters ?
For some reason the servers failed (need logs), and rerunning the test it can’t create a table (cause there’s no consensus).
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### Author:  [@dorian\_yugabyte](https://forum.yugabyte.com/u/dorian_yugabyte)
#### Post date: [October 7, 2019, 10:31am UTC](https://forum.yugabyte.com/t/linear-scalability-test/526/3 "2019-10-07T10:31:27Z")
> [@ivan\_s](#):
>
> Everything worked, but requests were distributed unevenly: [Screenshot by Lightshot](https://prnt.sc/pf9mzx) (n4 and n1 servers). **Why?**
That’s because n3,n4 have 2 leaders (see third column). Currently read requests go only to the leader tablet.
Do you need also to read from tablet peers ?
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### Author:  [@dorian\_yugabyte](https://forum.yugabyte.com/u/dorian_yugabyte)
#### Post date: [October 7, 2019, 10:36am UTC](https://forum.yugabyte.com/t/linear-scalability-test/526/4 "2019-10-07T10:36:43Z")
> [@dorian\_yugabyte](#):
>
> Do you need also to read from tablet peers ?
If you see, the same happens for write requests, they have 2 leaders and 2x write-ops.
Reading from peers may will have relaxed guarantees (not strongly consistent like leader).
If you need that functionality, can you please open a github issue ?