2015-01-05 15:12 GMT+01:00 sebb <seb...@gmail.com>: > On 5 January 2015 at 13:43, Stefan Bodewig <bode...@apache.org> wrote: >> On 2015-01-04, Kristian Rosenvold wrote: >> >>> Most surprising to me is that it seems like the overhead of lots of >>> small calls to RandomAccessFile.write seems to be a lot costlier than >>> I thought it would be. It seems like consolidating to a larger byte >>> array before calling write is a *lot* faster. >> >> This surprises me as well. > > Could be due to need to lock data in memory in native code. > This usually means data has to be copied to a safe buffer. > A single large copy will be faster than lots of small ones.
All of this disappears into native code pretty quickly so there might be OS-specific badness happening on OSX for all I know. I'll check on linux to see if there's a difference. But one thing is quite clear; if I do 1000 writes of 100 bytes each (for a grand total of 100K data) I can probably /copy/ the data at least 10 times in memory to make up for the difference in speed. Kristian --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org For additional commands, e-mail: dev-h...@commons.apache.org
