ISUCON10 Online event

Hello, This is Santosh.I participated in ISUCON2020 Online event, It was held on September 12,2020. Rules and regulations are mentioned on the official sites. please go through once(~5 minutes) http://isucon.net/archives/54704557.html Around 500~ teams participated on that day, It was fun as my first isucon! let's move to the technical side, There was an application given「isummo」、It was about finding chair(isu in japanese) by different conditions. The goal was to improve the search time and processing speed of isummo application.

lightly just go through the following; ・ Http://sinatrarb.com/ ・ New relic ruby version check-install,start mysql(may be it will helpful next time too) If any login issue with mysql just try this or follow stackoverflow↓ mysql -u root -p ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_passw

About coding language, you can choose any language Rust, Python, Go, Php or whatever you are comfortable with,I did with ruby as other team member were very familiar with it.Now the question is how to optimize our isummo app? ① Check all SQL queries -> Add index, as no index key was there eg. SQL -> select * from isuumo.chair where kind = 'some value' check kind is indexed or not ,if not -> KEY kind (kind) adding index is easy as soon as you find the query, and it's fasten our app to some level.(rank was going up & team was enjoying)

② Index based on order BY ASC OR DESC eg; select * from issumo.desk where some_condition order by popularity DESC; Please not here, order by have column by DESC, and the default index we add earlier will be ASC .To speedup execution of query make it, DESC INDEX, -> KEY popularity (popularity DESC) https://dev.mysql.com/doc/refman/8.0/en/descending-indexes.html After this our app performance increased a bit.

③ Next, find n+1,source code and try to fix that, this was a bit tough ,I tried but there was no such improvement in speed. Other things can be done on infrastructure side,as other member was doing that part I don't have much idea about it. Next isucon will try to cover up infra as well. Good luck everyone for next event!