UDP listener filter ECDS experiments---draft only

[yanjunxiang-google]

UDP listener filter ECDS experiments---draft only

This is continue for issue: #20049

UDP listener filter chain is created during listener creation. Thus ECDS may not work in UDP listener.

Created this draft PR so folks can discuss on it.

Signed-off-by: Yanjun Xiang [email protected]

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[yanjunxiang-google]

This PR is for folks involved to discuss ECDS on UDP listener.
Some experiments shows the config update to UDP ECDS listener filter is ignored due to UDP listener filter chain is created during listener creation. Thus config update is not taken in actual traffic handling. This may mean ECDS may not applicable to UDP listener filter.

Any way, throw this PR out so folks can refer this when discussing.

[yanjunxiang-google]

/wait

[soulxu]

This PR is for folks involved to discuss ECDS on UDP listener. Some experiments shows the config update to UDP ECDS listener filter is ignored due to UDP listener filter chain is created during listener creation. Thus config update is not taken in actual traffic handling. This may mean ECDS may not applicable to UDP listener filter.

Any way, throw this PR out so folks can refer this when discussing.

How about to recreate the udp listener filter when the ECDS updates the config?

[github-actions]

This pull request has been automatically marked as stale because it has not had activity in the last 30 days. It will be closed in 7 days if no further activity occurs. Please feel free to give a status update now, ping for review, or re-open when it's ready. Thank you for your contributions!

[github-actions]

This pull request has been automatically closed because it has not had activity in the last 37 days. Please feel free to give a status update now, ping for review, or re-open when it's ready. Thank you for your contributions!

[yanjunxiang-google]

This PR is for folks involved to discuss ECDS on UDP listener. Some experiments shows the config update to UDP ECDS listener filter is ignored due to UDP listener filter chain is created during listener creation. Thus config update is not taken in actual traffic handling. This may mean ECDS may not applicable to UDP listener filter.
Any way, throw this PR out so folks can refer this when discussing.

How about to recreate the udp listener filter when the ECDS updates the config?

Currently UDP listener filter chain is created during Envoy instance creation:

envoy/source/server/active_udp_listener.cc

Line 90 in 64a45c4

config_->filterChainFactory().createUdpListenerFilterChain(*this, *this);

If we recreated the UDP listener filter chian whenever ECDS updates received, which could be frequently, could this cause data loss? For example, when the UDP listener filters are processing live traffic, and ECDS updates received, what should Envoy do with that traffic?