Subject RE: [firebird-support] performance issue with firebird 3.0 embedded on linux
Author chen hsu
Thanks, Helen. Please see my replies inline. 

I am sure it is not 3.0 specific, 2.5 is the same. and the main issue is scalability, sequential transaction performance is actually pretty good, comparable to ESE store on windows I was comparing firebird against.  but when running multiple transactions in parallel, ESE perf increased from 4 tx/sec to 26 tx/sec (128 byte/record, 200 records per transaction, 6 transaction threads on 6 cores, which I expect the best, logical cpu/ht is not very useful performance-wise), while firebird decreased. These transactions do not write-conflict with each other. 

The basic flow of our code is like, first the main function creates a database connection, and spawns multiple threads, passing in the database connection. Each thread does this: create a transaction using the db connection, do insertion of data, and commit the transaction. Each thread measures its own elapsed time. 

Date: Wed, 15 Jun 2016 19:04:33 +1200
Subject: Re: [firebird-support] performance issue with firebird 3.0 embedded on linux

Wednesday, June 15, 2016, 5:58:39 PM, Karol B. wrote:

> test without details say nothing to me
> 1. Did you compare results with e.g. FB2.5 in on the same maschine with same configuration (FBConfig)
My project migrated from FB2.5 to FB3.0. I am pretty sure it is not 3.0 specific. 

> 2. What is your page size and type of HDD?
SSD. 512GB Samsung EVO 850. The file system is ext4, block size 4096. 

> 3. Do you have BOST feature enabled on CPU and HT? -- Boost?
Yes, Turbo boost and hyper threading are enabled. 

> 4. Did you compare results on GLOBAL TEMPORARY TABLE - i know this is not the same but can show some info?
Could you give me some details about how to use GLOBAL TEMPORARY TABLE? 

> 5. How do you test this times about your threads and how do you start them?
I used the monolithic time in code i.e. clock_gettime(CLOCK_MONOTONIC, &ts)  on each thread to calculate the elapsed time. should be high resolution. 

> 6. Exact version of FB

and 7. If on Windows, how did you go about configuring CpuAffinityMask?
- which processors did you intend to set it for and what was the value you configured?
It's on Linux, I read from document that multiple processors are by default enabled. but I anyway set CpuAffinityMask to 4095, but it seems no change to performance. 

- did you try to do this configuration whilst an engine instance was running, without restarting?
No. each time I change configuration, I restart the program.