Add Ansible automation section for Cassandra installation and updated Driver docs #89
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Add comprehensive documentation for installing Apache Cassandra using the AxonOps Ansible Collection, including: - Production-grade Cassandra deployment (standalone, without AxonOps) - Optional AxonOps monitoring integration (SaaS or self-hosted) - Multi-environment structure with hierarchical group_vars - Secrets management with Ansible Vault - SSL/TLS configuration for dev and production - Makefile-based workflow for consistent deployments - Rolling restart and upgrade procedures - Reference to AxonOps Cassandra Lab as ready-to-clone example - Pointer to Chef cookbook alternative Also updates installation methods comparison table to recommend Ansible for production cluster deployments.
millerjp
changed the title
Updated C#, C++, Ruby, and PHP driver links to use correct DataStax GitHub repositories. Also updated Ruby and PHP status to Maintenance.
- Add Java examples to Contact Points, Authentication, SSL/TLS sections - Add Java examples to all Prepared Statements anti-patterns - Add Java example to Error Handling section - Add comprehensive Java Driver Configuration System section covering Typesafe Config, HOCON, execution profiles, and programmatic config
- Driver auto-detects local DC from first contact point that responds - Explicit local DC only needed when using contact points from multiple DCs - Updated warning to info box explaining this behavior - Updated code comments to reflect auto-detection - Updated common mistakes table
hshimizu
reviewed
Dec 29, 2025
| (1 connection for thousands of concurrent queries) | ||
| ``` | ||
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| This means you **don't need large connection pools**. A single connection per host is often sufficient, and the driver manages this automatically. |
Contributor
There was a problem hiding this comment.
the language must be kept to scientific, engineering standards - so no "don't" - use "do not".
hshimizu
reviewed
Dec 29, 2025
| |---------|---------|----------| | ||
| | Multi-DC contact points without explicit local DC | Non-deterministic DC selection based on first responder | Set explicit `local_dc` or use contact points from single DC only | | ||
| | Using Round Robin | Ignores data locality, higher latency | Use Token-Aware + DC-Aware | | ||
| | Hardcoding contact points from one DC | If that DC is down, can't bootstrap | Include contact points from multiple DCs (with explicit local DC) | |
hshimizu
reviewed
Dec 29, 2025
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| **Python and the GIL**: Python's Global Interpreter Lock (GIL) means only one thread can execute Python bytecode at a time. In synchronous code, when your application waits for a Cassandra query to return, that thread is blocked and cannot process other requests. With async/await, the event loop can handle thousands of concurrent requests on a single thread by switching between tasks during I/O waits. This is particularly critical for web frameworks like FastAPI and aiohttp where blocking the event loop freezes your entire application. | ||
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| **Java and Thread Efficiency**: While Java doesn't have a GIL, creating threads is expensive (typically 1MB of stack memory each). Synchronous drivers require one thread per concurrent query, limiting scalability. Async operations with `CompletionStage` allow a small thread pool to handle many concurrent requests, reducing memory overhead and context-switching costs. This is especially valuable in reactive frameworks like Spring WebFlux and Vert.x. |
- Replace contractions with formal language per style guide:
- "don't" → "do not"
- "can't" → "cannot"
- "doesn't" → "does not"
- Add documentation for LWT/non-LWT mixing issues:
- New section in lightweight-transactions.md explaining why mixing
LWT with non-LWT operations is unsafe (Paxos clock conflicts)
- New troubleshooting page for LWT errors with diagnostics and
resolution steps
- Update common-errors index with LWT error category
- Add Common Errors section to Cassandra troubleshooting navigation
Contributor
Author
Addressed FeedbackThanks for the review! I have addressed all the comments: Style Guide FixesFixed contractions to use formal language:
Additional UpdatesAlso added new documentation for a LWT edge case (mixing LWT with non-LWT operations):
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hshimizu
approved these changes
Jan 3, 2026
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Add comprehensive documentation for installing Apache Cassandra using the AxonOps Ansible Collection, including:
Also updates installation methods comparison table to recommend Ansible for production cluster deployments.
Added more examples and information to the getting started section of the drivers