yes, one connection per database, any thread needs to access this database would create its own transaction.
To: [email protected] From: [email protected] Date: Wed, 15 Jun 2016 21:38:48 +0200 Subject: Re: [firebird-support] performance issue with firebird 3.0 embedded on linux Hi, do you mean that you share one connection between multiple threads? regards, Karol Bieniaszewski From: mailto:[email protected] Sent: Wednesday, June 15, 2016 5:55 PM To: [email protected] Subject: RE: [firebird-support] performance issue with firebird 3.0 embedded on linux 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.&nb sp; To: [email protected] From: [email protected] 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 Firebird-3.0.0.32483-0 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. HB
