Subject: Re: [Firebird-devel] [FB-Tracker] Created:
(CORE-5419) Index garbage collection on varchar
column causes server to hang

On 01/11/17 16:19, Vlad Khorsun wrote:
> 11.01.2017 15:09, Alex Peshkoff wrote:
>>>> Could you try fb2.5 (as i did) ?
>>> Will do.
>> On 2.5 I see approx 50% slowdown when GC is in progress. Same slowdown
>> is present when 'delete from test' is executed.
> Slowdown of what operation ?

I've read in 5419:

> This will cause the database server to become unstable and hang for
> minutes at a time(1-5 minutes), where no new connections is made and
> no other queries get processed.

So I've started the following script:
for i in `seq 10000`; do echo step $i; echo 'set stats on; select
current_time from rdb$database;'|./isql todel.fdb ; sleep 1; done


Current memory = 1146128
Delta memory = 101120
Max memory = 1154216
Elapsed time= 0.02 sec <<<<< this time
Cpu = 0.00 sec
Buffers = 75
Reads = 16
Writes = 0
Fetches = 282

>> Rather hard to say for sure cause execution time of test
>> connection varies from 0.01 sec to 0.02 sec for 2.5, not more. For
>> master it seems to be almost always 0.01.
> What is done in that test connection ? Could you try to create table
> and insert record into it ?

Will do.

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