A Multithreaded, Transaction-Based Locking Strategy for Containers Bob Steagall CppCon 2020 K E W B C O M P U T I N GCopyright © 2020 Bob Steagall K E W B C O M P U T I N G Overview • Sharing a container • Testing the STO-based solution • Summary CppCon 2020 - A Multi-threaded, Transaction-Based Locking Strategy for Containers 2Copyright © 2020 Bob Steagall K E W B C O M P U T I N G Sharing a Container Transaction-Based Locking Strategy for Containers 3Copyright © 2020 Bob Steagall K E W B C O M P U T I N G Sharing a Container – Avoiding Race Conditions • If all threads are readers… • No locking is required

Sharing ▪ Copied Value ▪ Thread-Specific Storage ▪ Future Dealing with Mutation ▪ Scoped Locking ▪ Strategized Locking ▪ Thread-Safe Interface ▪ Guarded Suspension Concurrent Architecture Active Object Sharing ▪ Copied Value ▪ Thread-Specific Storage ▪ Future Dealing with Mutation ▪ Scoped Locking ▪ Strategized Locking ▪ Thread-Safe Interface ▪ Guarded Suspension Concurrent Architecture Active Object Mutation ▪ Scoped Locking ▪ Strategized Locking ▪ Thread-Safe Interface ▪ Guarded Suspension Concurrent Architecture Active Object Monitor Object ReactorScoped Locking Scoped Locking is RAII applied

PostgreSQL Configuring Weblate to use PostgreSQL MySQL or MariaDB Unicode issues in MySQL Transaction locking Creating database in MySQL Configuring Weblate to use MySQL Other configurations Configuring outgoing Example - generating mo files in repository Translation process Suggestion voting Translation locking Additional information on source strings Strings prioritization Quaity check flags Visual context utf8mb4 by: ALTER DATABASE weblate CHARACTER SET utf8mb4; Transaction locking MySQL by default uses has different transaction locking scheme than other databases and in case you see errors like Deadlock

PostgreSQL Configuring Weblate to use PostgreSQL MySQL or MariaDB Unicode issues in MySQL Transaction locking Creating database in MySQL Configuring Weblate to use MySQL Other configurations Configuring outgoing Example - generating mo files in repository Translation process Suggestion voting Translation locking Additional information on source strings Strings prioritization Quaity check flags Visual context utf8mb4 by: ALTER DATABASE weblate CHARACTER SET utf8mb4; Transaction locking MySQL by default uses has different transaction locking scheme than other databases and in case you see errors like Deadlock

PostgreSQL Configuring Weblate to use PostgreSQL MySQL or MariaDB Unicode issues in MySQL Transaction locking Creating database in MySQL Configuring Weblate to use MySQL Other configurations Configuring outgoing Example - generating mo files in repository Translation process Suggestion voting Translation locking Additional information on source strings Strings prioritization Quaity check flags Visual context utf8mb4 by: ALTER DATABASE weblate CHARACTER SET utf8mb4; Transaction locking MySQL by default uses has different transaction locking scheme than other databases and in case you see errors like Deadlock

PostgreSQL Configuring Weblate to use PostgreSQL MySQL or MariaDB Unicode issues in MySQL Transaction locking Creating database in MySQL Configuring Weblate to use MySQL Other configurations Configuring outgoing Example - generating mo files in repository Translation process Suggestion voting Translation locking Additional information on source strings Strings prioritization Quaity check flags Visual context utf8mb4 by: ALTER DATABASE weblate CHARACTER SET utf8mb4; Transaction locking MySQL by default uses has different transaction locking scheme than other databases and in case you see errors like Deadlock

Example - generating mo files in repository Translation process Suggestion voting Translation locking Checks and fixups Custom automatic fixups Customizing checks Fine tuning existing checks Writing registration contain example.com as domain? Enable indexing offloading Enable OFFLOAD_INDEXING to prevent locking issues and improve performance. Don’t forget to schedule indexing in background job to keep the index translation for translating [Users, Managers] Can lock translation while translating (see Translation locking). Can add suggestion [Users, Managers, Guests] Can add new suggestions. Can use machine translation

Example - generating mo files in repository Translation process Suggestion voting Translation locking Checks and fixups Custom automatic fixups Customizing checks Fine tuning existing checks Writing registration contain example.com as domain? Enable indexing offloading Enable OFFLOAD_INDEXING to prevent locking issues and improve performance. Don’t forget to schedule indexing in background job to keep the index for translating [Users, Managers, Owners] Can lock translation while translating (see Translation locking). Can add suggestion [Users, Managers, Owners, Guests] Can add new suggestions. Can use machine

Example - generating mo files in repository Translation process Suggestion voting Translation locking Checks and fixups Custom automatic fixups Customizing checks Fine tuning existing checks Writing com/en/stable/ref/contrib/sites/] Enable indexing offloading Enable OFFLOAD_INDEXING to prevent locking issues and improve performance. Don’t forget to schedule indexing in background job to keep the index for translating [Users, Managers, Owners] Can lock translation while translating (see Translation locking). Can add suggestion [Users, Managers, Owners, Guests] Can add new suggestions. Can use machine

Example - generating mo files in repository Translation process Suggestion voting Translation locking Checks and fixups Custom automatic fixups Customizing checks Fine tuning existing checks Writing registration contain example.com as domain? Enable indexing offloading Enable OFFLOAD_INDEXING to prevent locking issues and improve performance. Don’t forget to schedule indexing in background job to keep the index translation for translating [Users, Managers] Can lock translation while translating (see Translation locking). Can add suggestion [Users, Managers, Guests] Can add new suggestions. Can use machine translation