Hi Andrew and Sushant Mahajan, Thank you for the review and suggestions.
AS1: You're absolutely right. I've now added the share.coordinator.append.max.buffer.size config with the same default value of 1*1024*1024 as you suggested. Sushant, thank you for highlighting the necessary changes to the CoordinatorRuntime. I've updated the implementation accordingly. Best, Lan At 2025-08-21 03:26:02, "Sushant Mahajan" <sushmah...@gmail.com> wrote: >Hi Lan, >This is a good idea, but as pointed out by Andrew, there are multiple >implementations composing the CoordinatorRuntime and perhaps will increase >in future so this must be addressed. > >Additionally, there will be changes needed in the CoordinatorRuntime >Builder interface itself, for example passing a buffer size config supplier >to fetch the specific config value passed by the coordinator specialization >as we should not refer to config name directly in the runtime. > >Thanks and regards, >Sushant Mahajan > >On Wed, 20 Aug 2025, 20:05 Andrew Schofield, < >andrew_schofield_j...@outlook.com> wrote: > >> Hi Lan, >> Thanks for the KIP. Decoupling these is a good idea. >> >> AS1: This is a change to the coordinator runtime and there >> are two concrete implementations, the group coordinator and >> the share coordinator. I think it would be equally valuable >> to have `share.coordinator.append.max.buffer.size`. >> The same default of 1*1024*1024 seems appropriate to me. >> >> Thanks, >> Andrew >> ________________________________________ >> From: Lan Ding <isdin...@163.com> >> Sent: 20 August 2025 14:57 >> To: dev@kafka.apache.org <dev@kafka.apache.org> >> Subject: Re: [DISCUSS] KIP-1196: Introduce >> group.coordinator.append.max.bytes config >> >> Hi Chia-Ping, >> >> >> >> Thanks for the feedback. The original configuration name was potentially >> ambiguous; >> >> it has therefore been renamed to >> `group.coordinator.append.max.buffer.size`. >> >> >> >> chia_00: >> >> Update the vaild values of group.coordinator.append.max.buffer.size to be >> >> less than message.max.bytes. >> >> >> >> chia_01: >> >> Yes, I agree. Make this config to be updated dynamically. >> >> >> >> chia_02: >> >> I agree with you. Since the buffer behavior is a soft limit, this change >> should >> >> not impact any existing functionality or require special compatibility >> measures. >> >> >> >> Best, >> >> Lan >> >> >> >> >> At 2025-08-18 00:54:15, "Chia-Ping Tsai" <chia7...@gmail.com> wrote: >> >hi Lan >> > >> >chia_00: >> > >> >The `group.coordinator.append.max.bytes` must be smaller than the max >> >message size; Otherwise, it could generate an invalid record >> > >> >chia_01: >> > >> >Since the max message size is a dynamic configuration, should we also make >> >`group.coordinator.append.max.bytes` dynamic? >> > >> >chia_02: >> > >> >Is compatibility necessary? The max buffer of the new coordinator is >> >currently transparent to users, so I don't think there are any users >> >explicitly setting the max message size to control the buffer used by the >> >new coordinator >> > >> >Best, >> >Chia-Ping >> > >> > >> >Lan Ding <isdin...@163.com> 於 2025年8月18日 週一 上午12:37寫道: >> > >> >> Hello everyone, I'd like to discuss a KIP regarding introducing a new >> >> configuration, >> >> group.coordinator.append.max.bytes Thank you! KIP link: >> >> https://cwiki.apache.org/confluence/x/hA5JFg Best, Lan Ding >>