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Permit loads while queries are running

A query may wait on a database-level lock, which could lead to a
deadlock between threads.
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1 parent 928f466 commit 007e50d8e5a900547471b6c4ec79d9d217682c5d @matthewd matthewd committed Oct 27, 2016
@@ -215,7 +215,11 @@ def explain(arel, binds = [])
# Executes the SQL statement in the context of this connection.
def execute(sql, name = nil)
- log(sql, name) { @connection.query(sql) }
+ log(sql, name) do
+ ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+ @connection.query(sql)
+ end
+ end
end
# Mysql2Adapter doesn't have to free a result after using it, but we use this method
@@ -86,7 +86,9 @@ def exec_stmt_and_free(sql, name, binds, cache_stmt: false)
end
begin
- result = stmt.execute(*type_casted_binds)
+ ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+ result = stmt.execute(*type_casted_binds)
+ end
rescue Mysql2::Error => e
if cache_stmt
@statements.delete(sql)
@@ -85,7 +85,9 @@ def result_as_array(res) #:nodoc:
# Queries the database and returns the results in an Array-like object
def query(sql, name = nil) #:nodoc:
log(sql, name) do
- result_as_array @connection.async_exec(sql)
+ ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+ result_as_array @connection.async_exec(sql)
+ end
end
end
@@ -95,7 +97,9 @@ def query(sql, name = nil) #:nodoc:
# need it specifically, you may want consider the <tt>exec_query</tt> wrapper.
def execute(sql, name = nil)
log(sql, name) do
- @connection.async_exec(sql)
+ ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+ @connection.async_exec(sql)
+ end
end
end
@@ -601,15 +601,21 @@ def execute_and_clear(sql, name, binds, prepare: false)
def exec_no_cache(sql, name, binds)
type_casted_binds = type_casted_binds(binds)
- log(sql, name, binds, type_casted_binds) { @connection.async_exec(sql, type_casted_binds) }
+ log(sql, name, binds, type_casted_binds) do
+ ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+ @connection.async_exec(sql, type_casted_binds)
+ end
+ end
end
def exec_cache(sql, name, binds)
stmt_key = prepare_statement(sql)
type_casted_binds = type_casted_binds(binds)
log(sql, name, binds, type_casted_binds, stmt_key) do
- @connection.exec_prepared(stmt_key, type_casted_binds)
+ ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+ @connection.exec_prepared(stmt_key, type_casted_binds)
+ end
end
rescue ActiveRecord::StatementInvalid => e
raise unless is_cached_plan_failure?(e)
@@ -191,27 +191,29 @@ def exec_query(sql, name = nil, binds = [], prepare: false)
type_casted_binds = type_casted_binds(binds)
log(sql, name, binds, type_casted_binds) do
- # Don't cache statements if they are not prepared
- unless prepare
- stmt = @connection.prepare(sql)
- begin
- cols = stmt.columns
- unless without_prepared_statement?(binds)
- stmt.bind_params(type_casted_binds)
+ ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+ # Don't cache statements if they are not prepared
+ unless prepare
+ stmt = @connection.prepare(sql)
+ begin
+ cols = stmt.columns
+ unless without_prepared_statement?(binds)
+ stmt.bind_params(type_casted_binds)
+ end
+ records = stmt.to_a
+ ensure
+ stmt.close
end
+ else
+ cache = @statements[sql] ||= {
+ stmt: @connection.prepare(sql)
+ }
+ stmt = cache[:stmt]
+ cols = cache[:cols] ||= stmt.columns
+ stmt.reset!
+ stmt.bind_params(type_casted_binds)
records = stmt.to_a
- ensure
- stmt.close
end
- else
- cache = @statements[sql] ||= {
- stmt: @connection.prepare(sql)
- }
- stmt = cache[:stmt]
- cols = cache[:cols] ||= stmt.columns
- stmt.reset!
- stmt.bind_params(type_casted_binds)
- records = stmt.to_a
end
ActiveRecord::Result.new(cols, records)
@@ -229,7 +231,11 @@ def last_inserted_id(result)
end
def execute(sql, name = nil) #:nodoc:
- log(sql, name) { @connection.execute(sql) }
+ log(sql, name) do
+ ActiveSupport::Dependencies.interlock.permit_concurrent_loads do
+ @connection.execute(sql)
+ end
+ end
end
def begin_db_transaction #:nodoc:

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