a437b219ac
Param flush_on_reconnect is very risky to use on production deployments. It can cause exponential raising of connections to memcached servers. Moreover this option makes sense only in keystone's oslo.cache config. This patch is moving flush_on_reconnect from code to oslo.cache config block to be configurable. Co-Authored-By: Hervé Beraud <hberaud@redhat.com> Change-Id: I8e6826bfb2c85e7ceed03e1667bd6a06b3dff469 Closes-Bug: #1888394
23 lines
1020 B
YAML
23 lines
1020 B
YAML
---
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fixes:
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- |
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[`bug 1888394 <https://bugs.launchpad.net/oslo.cache/+bug/1888394>`_]
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If a memcache server disappears and then reconnects when multiple memcache
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servers are used (specific to the python-memcached based backends) it is
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possible that the server will contain stale data. To avoid this, param
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flush_on_reconnect was used in code.
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But unfortunatelly this option is causing another issue.
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If memcache server disappears, or client had broken connection to memcache server,
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clients start to flush server on reconnect.
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This means that network connections will go UP and can cause server to be overloaded
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until memcache will be unresponsive.
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Simply said this option can cause loop of flushs and overloaded memcached servers.
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This change is moving optional parameter `flush_on_reconnect` to oslo.cache config.
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features:
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- Configuration option ``memcache_pool_flush_on_reconnect`` added to control
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if flush will be sent to memcached server after reconnect.
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