[WIP] Used blocking operation blPop for locking

[stekycz]

Proof of concept

Brings better performance without no need of using active waiting for the lock.

Please, validate it again and again. I have spent a few hours validating it so I can miss something important.

[JakubKontra]

Huh, I thinks its good idea! It seems to be very good! Good Job Martin!

[fprochazka]

Great work!

[stekycz]

Questions

• Should I use constants for :control and :timeout string?
• Is it ok to have so many keys matching in test? I guess it is because of expiration however I would like to know your opinion.

[stekycz]

• :timeout does not have to be timestamp, it should be random inserting instead
• rename :control to more appropriate name (perhaps :exist or :in-use) - maybe use value 1?

[fprochazka]

@stekycz I have no idea, I won't have time to think about it sooner than this sunday.

[stekycz]

@fprochazka Take a time. I also want to think about it again :-)

[matej21]

• session write should fail if lock expires