Medium or low processor activity during indexing
(typically 70% or less) indicates that IBM Content Search Services is not using the processor
optimally. |
- Documents are not submitted fast enough for indexing. To validate,
monitor queues and check whether the input queue size is low, relative
to the configured input queue size. If so, ensure that the client
is pushing documents fast enough to the server.
- There is insufficient memory on the computer on which the IBM Content Search Services server runs. Monitor memory
consumption on the server computer. Consider reserving memory or increasing
the maximum heap size.
- Indexing is constrained by I/O activity. The disk I/O is a bottleneck.
Monitor disk activity and see the next section ("Too much disk activity
during indexing") for recommendations.
- The IBM Content Search Services server
configuration is not optimal. For example, the number of preprocessing
threads, tokenizers, or indexing threads might be too low. See the
documentation for each parameter for recommendations on optimal settings.
- The queue size is too small. Monitor queues and ensure that indexing
progresses smoothly. Also ensure that the queue size is appropriate
for your heap memory allocation and the size of documents that you
are processing. Note that increasing the queue size too high can have
a negative impact on performance.
|
Too much disk activity during indexing (typically
greater than 80%) can indicate that the disk I/O is a bottleneck |
- The disk is too slow. Some IBM Content Search Services files
(such as program files, configuration files, logs, or collection data)
might be stored on a remote disk, a disk with high latency, or disk
with limited throughput. For the temporary folder, consider using
a RAM drive, increasing the disk block size, or using a faster disk.
- Other programs are using the disk in parallel to IBM Content Search Services. To determine whether this
is a problem, shut down other applications.
- There is insufficient available memory. Consider reserving memory
for the IBM Content Search Services computer,
or increasing the maximum heap size.
- Multiple collections are being indexed simultaneously. If this
is the cause, consider storing the data for different collections
on different disks.
- Index merge operations occur too frequently. Consider increasing
the values of the following indexing parameters: BufferSize, MergeFactor,
and MaxMergeMB.
|
The IBM Content Search Services server
consumes most of the heap memory allocation. When IBM Content Search Services memory consumption is high
(even without out-of-memory errors), performance can degrade due to
frequent JVM garbage collection calls and more expensive memory management. |
- Not enough heap memory is allocated to IBM Content Search Services. Consider increasing the
heap memory by increasing the value of the maxHeapSize parameter.
Ensure that you have enough available memory on the IBM Content Search Services computer.
- Queue size setting might be too high. Check the queue size settings.
If necessary, reduce the queue sizes.
- Too many preprocessing and indexing threads are defined. Check
how many preprocessing and indexing threads are defined. If necessary,
reduce the number of threads.
- Too many collections are indexed concurrently. If possible, limit
the number of concurrently indexed collections.
|
Overall memory consumption on the IBM Content Search Services computer is very high, or
higher than the physical memory. Operating system memory management
(using virtual memory, garbage collection, and so on) starts to have
a noticeable effect on the overall system performance, even when out-of-memory
errors do not occur. |
- Too many applications are running. Consider shutting down applications
or distributing applications to different computers.
- Physical memory is too small. Increase the physical memory or
reserve more physical memory (if applicable).
|
CPU consumption is very high and search times
are very slow when indexing and searching on the same computer. |
See Limiting IBM Content Search Services resource consumption. |