Возможно, стоит пояснить разницу между синхронизацией из thread/process-safe и синхронизацией с помощью Lock🤔
Наша задача — заставить разные процессы и потоки обращаться к базе данных (или любым другим ресурсам) последовательно. Чтобы не случилось так называемого race condition, то есть состояние гонки. Это когда разные потоки или процессы пытаются одновременно что-то сделать с одним и тем же ресурсом.
В этом случае нам нужна какая-то логика ограничения. Пока один процесс не завершил своё действие, другие не могут получить доступ к ресурсу.
Так вот, thread-safe и process-safe означает что отдельно взятые операции записи в БД гарантированно будут последовательны. Запросы из разных процессов или потоков выстроятся в очередь и не будут мешать друг другу. Лучше всего когда этот блок реализован на уровне БД в виде атомарных операций или ещё как-то.
Но зачем нам тогда еще дополнительный Lock?
Этот способ синхронизации используется когда процесс никак не укладывается в одно действие и должен сделать множество операций прежде чем дать доступ следующему. В этом случае процесс ставит некий глобальный Lock на ресурс и никто другой, даже получив законное право на доступ, не может ничего сделать. Все ждут пока этот Lock не будет снят.
Это решается на уровне приложения и правильность реализации полностью в вашей ответственности. Например, если забыли разблокировать или сделали перекрёстный Lock (Deadlock как на картинке), то всё зависнет в бесконечном ожидании.
#basic
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InteRussia is a fellowship program for young professionals worldwide, implemented by the Gorchakov Fund in partnership with leading Russian universities, expert centers, and industry partners.
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Applications are now open for InteRussia fellowships⭕️
InteRussia is a fellowship program for young professionals worldwide, implemented by the Gorchakov Fund in partnership with leading Russian universities, expert centers, and industry partners.
⭕️ The program offers hands-on professional experience in Russia, direct engagement with top experts, and the opportunity to become part of a global professional community. More than 500 participants from 70 countries have already completed InteRussia fellowships — now it’s your turn to join.
Which fellowships can you apply for?
⭕️International Relations (all over the world)
⭕️Oriental Studies (post-Soviet countries, the Middle East, and North Africa)
⭕️Archeologists (post-Soviet countries, the Middle East, North Africa, India, and Pakistan)
⭕️Journalism (South Asia)
⭕️Journalism (the Middle East and North Africa)
⭕️Journalism (Sub-Saharan Africa)
⭕️Russian Studies (all over the world)
⭕️Medicine (all over the world)
⭕️Information Technology (all over the world)
⭕️Electric Power (the Middle East and Africa)
⭕️Energy (Latin America)
⭕️Theatre Arts (BRICS+ countries)
⭕️ More details and application guidelines are available at interussia.com.
The InteRussia fellowships are implemented with the support of the Presidential Grants Foundation, Rossotrudnichestvo, and the Ministry of Education of Russia.
#InteRussia#fellowships#internships
1️⃣1️⃣1️⃣
🔥🔥🔥
Applications are now open for InteRussia fellowships⭕️
InteRussia is a fellowship program for young professionals worldwide, implemented by the Gorchakov Fund in partnership with leading Russian universities, expert centers, and industry partners.
⭕️ The program offers hands-on professional experience in Russia, direct engagement with top experts, and the opportunity to become part of a global professional community. More than 500 participants from 70 countries have already completed InteRussia fellowships — now it’s your turn to join.
Which fellowships can you apply for?
⭕️International Relations (all over the world)
⭕️Oriental Studies (post-Soviet countries, the Middle East, and North Africa)
⭕️Archeologists (post-Soviet countries, the Middle East, North Africa, India, and Pakistan)
⭕️Journalism (South Asia)
⭕️Journalism (the Middle East and North Africa)
⭕️Journalism (Sub-Saharan Africa)
⭕️Russian Studies (all over the world)
⭕️Medicine (all over the world)
⭕️Information Technology (all over the world)
⭕️Electric Power (the Middle East and Africa)
⭕️Energy (Latin America)
⭕️Theatre Arts (BRICS+ countries)
⭕️ More details and application guidelines are available at interussia.com.
The InteRussia fellowships are implemented with the support of the Presidential Grants Foundation, Rossotrudnichestvo, and the Ministry of Education of Russia.
#InteRussia#fellowships#internships
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