![]() Keep in mind that buffers should be registered in the same order in which locks are to be obtained on them during replay. Registrations of buffers (step 2) and modifications of page images (step 3) can be mixed freely, i.e., both steps may be repeated in any sequence. Exclusive lock must be held on each target buffer from before GenericXLogRegisterBuffer() until after GenericXLogFinish(). However, it remains the caller's responsibility to pin/unpin and lock/unlock the buffers at appropriate times. In other words, code that makes generic WAL records should never call BufferGetPage() for itself. ![]() No direct modifications of buffers are allowed! All modifications must be done in copies acquired from GenericXLogRegisterBuffer(). Please note the following points when using the generic WAL record facility: This will discard all changes to the page image copies. WAL record construction can be canceled between any of the above steps by calling GenericXLogAbort(state). GenericXLogFinish(state) - apply the changes to the buffers and emit the generic WAL record. GenericXLogRegisterBuffer can be repeated if the WAL-logged action needs to modify multiple pages.Īpply modifications to the page images obtained in the previous step. Typically this flag would be set if the page is new or has been rewritten completely. Currently the only such flag is GENERIC_XLOG_FULL_IMAGE, which indicates that a full-page image rather than a delta update should be included in the WAL record. (Do not modify the buffer's contents directly.) The third argument is a bit mask of flags applicable to the operation. This function returns a pointer to a temporary copy of the buffer's page, where modifications should be made. Page = GenericXLogRegisterBuffer(state, buffer, flags) - register a buffer to be modified within the current generic WAL record. (this.State = GenericXLogStart(relation) - start construction of a generic WAL record for the given relation. This.poolCluster = mysql.createPoolCluster() This.waitingForAutoFaileOverSwitch = false ![]() To prevent any doubt, also feel free to check out an AWS-provided example that closes connections here (linked to from docs), or another one in the AWS Compute Blog here. Many applications, including those built on modern serverless architectures, can have a large number of open connections to the database server, and may open and close database connections at a high rate, exhausting database memory and compute resources. It is responsible for helping by managing connection multiplexing/pooling & sharing automatically for applications that need it.Īn example of an application that needs it is clearly mentioned in the AWS docs: The proxy is not responsible for closing local connections that you make nor should it be. The point is that your Amazon RDS Proxy instance maintains a pool of established connections to your RDS database instances for you - it sits between your application and your RDS database. Keep DB resources tied up with many open connections & you'll find yourself needing more vCPUs for your DB instance which then results in a higher RDS proxy price tag.Īnd if I should close the connection, then what's the point of using an RDS Proxy in the first place? Closing database connections is being a good database client. Connections that are not explicitly closed might not be added or returned to the pool. The rule of thumb is to open connections as late as possible & close DB connections as soon as possible. You should not leave database connections open regardless of if you use or don't use a database proxy.Ĭonnections are a limited and relatively expensive resource. Should I close the connection after executing my queries or leave it open for the RDS Proxy to handle? The RDS proxy sits between your application and the database & should not result in any application change other than using the proxy endpoint.
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