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Aleksey Yeschenko commented on CASSANDRA-15410: ----------------------------------------------- I welcome this change in principle, but it makes me feel a little uneasy. Specifically, it relies implicitly on how the method is used two levels of abstraction up, and feels slightly brittle to me. I wonder if you'd be open instead to a slightly less efficient but, importantly, still resize-avoiding alternative: modify {{CBUtil#writeString()}} (and {{CBUtil#writeLongString()}} while at it, just for consistency sake) to explicitly calculate the precise size of encoded string using {{TypeSizes#encodedUTF8Length()}} method, and then pass that value to {{ByteBufUtil#reserveAndWriteUtf8()}}. This way, yes, you would effectively calculate the size of the string twice, but the abstraction won't leak assumptions, and will still avoid unnecessary resizing. > Avoid over-allocation of bytes for UTF8 string serialization > ------------------------------------------------------------- > > Key: CASSANDRA-15410 > URL: https://issues.apache.org/jira/browse/CASSANDRA-15410 > Project: Cassandra > Issue Type: Improvement > Components: Messaging/Client > Reporter: Yifan Cai > Assignee: Yifan Cai > Priority: Normal > Fix For: 4.0 > > > In the current message encoding implementation, it first calculates the > `encodeSize` and allocates the bytebuffer with that size. > However, during encoding, it assumes the worst case of writing UTF8 string to > allocate bytes, i.e. assuming each letter takes 3 bytes. > The over-estimation further leads to resizing the underlying array and data > copy. -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org For additional commands, e-mail: commits-h...@cassandra.apache.org