Describe How and Why NGINX Uses Shared Memory Zones F5N1 Practice Questions (Page 3)

Questions 11–15

1. 11foundation · easy

   How does NGINX ensure that multiple worker processes can access the same shared memory zone efficiently?

   • ABy using a file lock to serialize access to a disk file
   • BBy mapping the same physical memory region into the address space of each worker process
   • CBy using a separate copy of the zone for each worker and synchronizing them via the network
   • DBy storing the data in a database that all workers query
   Reveal Solution Discussion Select an answer first
2. 12foundation · easy

   What is a potential limitation of shared memory zones in NGINX?

   • AThey are slower than using a local file for data storage
   • BThey can only be used with a single worker process
   • CThey consume memory that is not available for other purposes
   • DThey require a separate database to store the data
   Reveal Solution Discussion Select an answer first
4. 13application · medium

   An NGINX administrator is troubleshooting a performance issue where cache hits are inconsistent across worker processes. The cache is configured in the http block. What is the most likely reason for the inconsistency, and what should be done to fix it?

   • AThe worker_processes directive is set too high, causing cache thrashing. Reduce the number of workers to 2.
   • BThe cache zone is not defined as a shared memory zone, so each worker maintains its own cache. Define the cache with a shared memory zone using the proxy_cache_path directive with a keys_zone parameter.
   • CThe proxy_cache_valid directive is misconfigured, causing entries to expire too quickly. Increase the validity period.
   • DThe cache is stored on a local disk, which is not accessible to all workers. Move the cache to a network filesystem.
   Reveal Solution Discussion Select an answer first
5. 14application · medium

   A company runs a website that experiences sudden traffic spikes. They want to use NGINX caching to reduce the load on their backend servers. The administrator has configured a cache with a shared memory zone. What additional directive is required to actually enable caching for a specific location?

   • Aproxy_pass in the location block, forwarding requests to the backend.
   • Badd_header in the location block, adding cache control headers.
   • Cproxy_cache in the location block, referencing the cache zone defined by proxy_cache_path.
   • Dproxy_cache_valid in the http block, setting the cache validity period.
   Reveal Solution Discussion Select an answer first
6. 15expert · hard

   An NGINX administrator is considering whether to use a shared memory zone for a new feature that tracks user sessions. The application has a very large number of unique users (millions) and sessions are short-lived. What is the primary trade-off the administrator should consider?

   • ANetwork latency versus the ability to synchronize session data between servers.
   • BCPU usage versus the ability to compress session data.
   • CMemory usage versus the ability to share session data across all worker processes.
   • DDisk I/O versus the ability to persist session data across restarts.
   Reveal Solution Discussion Select an answer first