Hi Sijie,

Thanks for your helpful reply. My testing has shown that you're correct, writes 
above 1MB fail with a NotEnoughBookies exception. I must have tested a 
compressed version of data previously.

Onyx uses a state changelog using small state updates and wish to occasionally 
compact these ledgers into a new ledger, with a single state entry. This would 
allow for fast recovery of the latest state when nodes fail. Therefore latency 
isn't a big issue. We may consider chunking the writes into multiple entries to 
deal with this limitation. 

Thanks again,

Lucas


> On 12 Dec 2015, at 5:02 AM, Sijie Guo <[email protected]> wrote:
> 
> Lucas,
> 
> I think there is a hard limitation on entry size, which is 1MB. Did you 
> successfully write entries that are large than 1MB?
> 
> In bookkeeper, the entry is unit of durability. It potentially has latency 
> impacts, as it has to fsync all 1MB to disk before acknowledge. If your 
> traffic is comprised with constant MBs, that's probably. If you traffic is 
> mixed with small entries, those small entries' add latency might be impacts. 
> Other than that, I didn't see too much concerns. 
> 
> Do you have any test results to share with the community about adding MB 
> entries?
> 
> - Sijie
> 
>> On Thu, Dec 10, 2015 at 6:57 AM, Lucas Bradstreet 
>> <[email protected]> wrote:
>> Hi all,
>> 
>> Does anyone have any experience with large ledger entry writes (in the
>> multiple MB range)? My testing has shown that these writes appear to
>> work, but I'm interested in whether there are any operational concerns
>> I should be aware of.
>> 
>> Thank you,
>> 
>> Lucas
> 

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