Resolving OpenObserve Deadlock During Stream Stats Reset
Hey there, OpenObserve users and enthusiasts! If you've ever run into a deadlock detected error, especially when trying to reset stream-stats in OpenObserve, you know how frustrating it can be. This article is all about helping you understand, diagnose, and ultimately resolve this tricky situation. We'll dive deep into what a deadlock is, why it might be happening in your OpenObserve environment, and what steps you can take to fix it and prevent it from recurring. Our goal is to make sure your OpenObserve instance runs smoothly, keeping your data flowing and your systems observable. So, let's get into it and make sure those stream-stats resets go off without a hitch!
Understanding the OpenObserve Deadlock Challenge
When we talk about an OpenObserve deadlock, we're primarily referring to a situation where two or more operations in your database environment are stuck, each waiting for the other to release a resource. In the context of OpenObserve, specifically when attempting to reset stream stats, this can be a real showstopper. The openobserve reset -c stream-stats command is super important for re-calculating critical metrics about your data streams, which helps maintain the accuracy and efficiency of your observability platform. However, as some of you guys might have experienced, this crucial operation can sometimes halt with a deadlock detected error, leaving you scratching your head.
Why is this a big deal? Well, accurate stream-stats are vital for OpenObserve's performance and for providing you with reliable insights into your data. If these stats aren't correctly computed or updated due to a deadlock, it can lead to stale data, inaccurate dashboards, or even broader performance degradation. The provided logs clearly indicate a deadlock detected issue during the execution of file list remote calculate stats failed: set stream stats error: SqlxError# error returned from database: deadlock detected. This specific message points directly to a contention problem within the database layer when the system tries to update stream statistics. It's often related to how concurrent database operations manage locks on tables or rows. When two processes need the same resource but in a conflicting order, they end up in a perpetual waiting game – a deadlock.
Compounding this, the logs also give us a helpful warning: ZO_CALCULATE_STATS_STEP_LIMIT_SECS good to be at least 3600 for stats reset. This isn't just a friendly suggestion; it's a strong hint that the OpenObserve stream stats reset process might be trying to do too much work in one go, increasing the likelihood of locking conflicts. When transactions are long-running or involve a large number of rows, they hold locks for extended periods, making other operations more prone to waiting and, eventually, deadlocking. The sheer volume of Loading disk cache messages—over 64,000 files being processed—suggests that this stream-stats reset is a resource-intensive operation that touches a significant portion of your data. This extensive loading and subsequent database updates make the system highly susceptible to locking issues, especially if other OpenObserve components are also actively writing or reading from the same tables. Understanding this core challenge is the first step towards a robust solution, ensuring your OpenObserve deployment remains stable and efficient.
Deep Dive into the OpenObserve Reset Process and Log Analysis
Let's meticulously dissect the provided logs to truly grasp what's happening during this OpenObserve deadlock scenario. The log output is a treasure trove of information, detailing the steps OpenObserve takes when reset -c stream-stats is initiated and where things go awry. Understanding each line helps us pinpoint the specific moments of vulnerability. The process kicks off with an error: [2025-11-18T02:06:32Z ERROR config::config] Failed to load config Config init: No .env file found during default discovery. While not directly related to the deadlock, it's an important initial observation that indicates a potential configuration oversight. Properly configuring your .env file is crucial for OpenObserve's operation, even if it doesn't cause this specific panic, it's a general best practice for system health.
Following this, we see a massive amount of activity related to cache loading. Lines like [2025-11-18T02:06:32Z INFO infra::cache::file_data::disk] Loading disk cache start and hundreds of subsequent Loading disk cache X messages (culminating in total files: 64514) tell us that OpenObserve is busy bringing a significant amount of file metadata into memory. This disk cache loading is a crucial preparation step, as stream-stats likely relies on this metadata to calculate accurate statistics. Processing over 64,000 files is no small feat and takes time and resources. During this period, the system is actively interacting with the file system and potentially preparing data that will eventually be written to the database. This intensive I/O and data preparation phase sets the stage for potential database contention later on.
Next up, the logs show some critical database operations and service initializations. We see Shutting down DDL connection pool, Organizations users Cached, Stream schemas Cached 281 schemas, and Stream schemas Cached 274 streams. These messages indicate that OpenObserve is initializing or refreshing its database-related caches and connections, preparing to interact with its persistent storage. The successful connection to NATS (connected successfully server=4222) also confirms that the messaging layer is operational. However, the real culprits begin to emerge with the WARN sqlx::query entries. Two statements are flagged for being slow: a SELECT query on the file_list table took 1.246835315s and an INSERT into stream_stats took 1.001085967s. Both exceeded the default 1-second slow_threshold.
These slow SQL statements are critical indicators of potential performance bottlenecks and are often direct precursors to deadlocks. The SELECT query, which groups by stream and calculates min_ts, max_ts, file_num, records, and sizes, is likely a major component of the stream-stats calculation process. If this query takes over a second, it implies it's either processing a large volume of data, lacks optimal indexing, or is experiencing contention itself. The subsequent INSERT into stream_stats is equally concerning. An INSERT into a stats table taking over a second, especially when trying to initialize entries with zeros, suggests contention on the stream_stats table itself. When these queries are slow, they hold database locks for longer periods. If another process simultaneously tries to acquire a conflicting lock on the same file_list or stream_stats table, that's where the deadlock detected message comes into play. The thread 'main' panicked at /openobserve/src/cli/basic/cli.rs:263:26: file list remote calculate stats failed: set stream stats error: SqlxError# error returned from database: deadlock detected is the final confirmation – the system crashed because two or more transactions got stuck in a circular dependency, each waiting for the other, making it a clear regression in this version (v0.16.2).
Diagnosing the Deadlock: Common Causes and OpenObserve's Context
Alright, let's talk about diagnosing this specific OpenObserve deadlock – it's like being a detective, piecing together clues from the logs. When a database yells