LibUV event will use the best available polling method on a system, kind
of like aria2 does already with the different *EventPoll
implementations.
However, libuv may support different/newer polling mechanisms; for
example on Windows it will use IO Completion Ports which are superior to
select() ;)
Now dedicated ConnectCommand handles connection establishment. It
checks whether connection is established or not. It also handles
backup connection. The next Command creation is abstracted using
ControlChain struct template.
Saved sessions may very large, as in hundreds and even thousands of
megabyte when dealing with large queues.
Add support to save and reload sessions to gzipped files, when libz is
available.
The session serializer will output gzipped contents when the file ends
with .gz, while the input file reader (UriListParser) will accept
whatever is thrown at it.
--save-session-interval option saves error/unfinished downloads to a
file specified by --save-session option every SEC seconds. If 0 is
given, file will be saved only when aria2 exits.
This change replaces the current 64 bit sequential GID with 64 bits
random bytes GID in an attempt to support persistent GID. Internally,
the GID is stored as uint64_t. For human representation and RPC
interface, GID is represented as 16 bytes hex string. For console
readout, 16 bytes are too long, so it is abbreviated to first 6 bytes.
When querying GID in RPC calls, user can speicfy the prefix of GID as
long as the prefix is shared by more than 1 GID entries.
This option enables disk cache. If SIZE is 0, the disk cache is
disabled. This feature caches the downloaded data in memory, which
grows to at most SIZE bytes. The cache storage is created for aria2
instance and shared by all downloads. The one advantage of the disk
cache is reduce the disk seek time because the data is written in
larger unit and it is reordered by the offset of the file. If the
underlying file is heavily fragmented it is not the case.
The old implementation calculates download/upload statistics for a
RequestGroup by summing up all PeerStat objects. For global
statistics, those are summed together. This clearly incurs runtime
penalty and we introduced some kind of caching which updates
statistics every 250ms but it did not work right.
This change removes all these aggregation code, and instead makes
RequestGroup and RequestGroupMan objects hold NetStat object and
download/upload bytes are directly calculated by thier own NetStat.
This is far more simplar than the old way and less runtime penalty and
brings more accuracy.
--file-allocation option can now take new value 'trunc'. 'trunc' uses
ftruncate() system call or platform-specific counterpart to truncate a
file to a specified length.
The help messages shown when argument error were redesigned and less
verbose now. When unknown or ambiguous option is given, show
suggestions like "Did you mean...". Some constant values related to
levenstein distance are borrowed from git help.c.
This feature stops application when process PID is not running. This
is useful if aria2 process is forked from a parent process. The parent
process can fork aria2 with its own pid and when parent process exits
for some reason, aria2 can detect it and shutdown itself.
The code which detects whether or not given process PID is running is
contributed by Emmanuel Engelhart.
Tatsuhiro Tsujikawa