| Sounds good to me as well, so +1 for opening a jira and discussing how to do it.
I also wanted to point out that BOOKKEEPER-11 will be changing the client API (adding new calls, not changing existing ones). Anyone interested or with an opinion, please have a look.
-Flavio
On Jul 13, 2011, at 11:34 PM, Utkarsh Srivastava wrote: Seems reasonable to me. Is it worth using ByteBuffer instead of passing around offset and limit separately? Utkarsh On Wed, Jul 13, 2011 at 9:30 AM, Ivan Kelly < [email protected]> wrote: I'm having an issue with the LedgerHandle#addEntry api.
[1] best illustrates it. I'm buffering namenode transactions in the stream
and only transmitting when either flush is called or I have enough data to
pass my threshold. This means I have a byte buffer in my class which I fill
up as new transactions come in. When I transmit, I set this buffer as an
entry to bookkeeper. I.e. N whole namenode transactions will be contained in
1 single bk entry.
The problem is this byte buffer (DataOutputBuffer in this case). I reuse
the same buffer over and over. But this buffer has a fixed size. If I
transmit before it is full, the whole buffer size will be transmitted
anyhow. If the buffer is being reused, this will retransmit old transactions
out of order. For example, in the first use, the buffer fills with,
[a,b,c,d,e] and adds this as an entry and resets the byte buffer. Then
transaction f is added and flushed, in this case [f,b,c,d,e] is not
transmitted.
What I need is the ability to set offset and length in the byte[] passed to
addEntry. Is there a reason this wasn't added in the initial implementation?
If not, and if you agree this is a valid usecase, ill open a JIRA and add
this functionality. Im getting around this now by doing an extra
Array.copyOf which is less than ideal.
-Ivan
[1]
https://github.com/ivankelly/hadoop-common/blob/HDFS-1580-BK/hdfs/src/java/org/apache/hadoop/hdfs/server/namenode/bkjournal/BookKeeperEditLogOutputStream.java#L149
flaviojunqueira research scientist [email protected]direct +34 93-183-8828 avinguda diagonal 177, 8th floor, barcelona, 08018, esphone (408) 349 3300 fax (408) 349 3301
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