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If you have a substantial TeamCity installation, please check you have appropriate memory settings as a first step.
Collect Data
Take During the slow operation, take several thread dumps of the slow process (see below for thread dump taking approaches) with 5-10 seconds interval. If the slowness continues, please take several more thread dumps (e.g. 3-5 within several minutes) and then repeat after some time (e.g. 10 minutes) while the process is still being slow.
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