summaryrefslogtreecommitdiff
path: root/docs
diff options
context:
space:
mode:
authorDaniel Stenberg <daniel@haxx.se>2019-07-20 19:14:00 +0200
committerDaniel Stenberg <daniel@haxx.se>2019-07-20 19:14:30 +0200
commit47b9930df9e68a524a0072bf912d8161807afb5e (patch)
treeb05d698662b19c1337a7b3958526b6f223e61ba4 /docs
parentb88940850002a3f1c25bc6488b95ad30eb80d696 (diff)
downloadcurl-47b9930df9e68a524a0072bf912d8161807afb5e.tar.gz
docs/PARALLEL-TRANSFERS: added
Diffstat (limited to 'docs')
-rw-r--r--docs/Makefile.am1
-rw-r--r--docs/PARALLEL-TRANSFERS.md58
2 files changed, 59 insertions, 0 deletions
diff --git a/docs/Makefile.am b/docs/Makefile.am
index e34b80488..ed6a212e0 100644
--- a/docs/Makefile.am
+++ b/docs/Makefile.am
@@ -67,6 +67,7 @@ EXTRA_DIST = \
KNOWN_BUGS \
LICENSE-MIXING.md \
MAIL-ETIQUETTE \
+ PARALLEL-TRANSFERS.md \
README.cmake \
README.md \
README.netware \
diff --git a/docs/PARALLEL-TRANSFERS.md b/docs/PARALLEL-TRANSFERS.md
new file mode 100644
index 000000000..dc317f5f5
--- /dev/null
+++ b/docs/PARALLEL-TRANSFERS.md
@@ -0,0 +1,58 @@
+# Parallel transfers
+
+curl 7.65.0 introduces support for doing multiple transfers simultaneously; in
+parallel.
+
+## -Z, --parallel
+
+When this command line option is used, curl will perform the transfers given
+to it at the same time. It will do up to `--parallel-max` concurrent
+transfers, with a default value of 50.
+
+## Progress meter
+
+The progress meter that is displayed when doing parallel transfers is
+completely different than the regular one used for each single transfer.
+
+ It shows:
+
+ o percent download (if known, which means *all* transfers need to have a
+ known size)
+ o precent upload (if known, with the same caveat as for download)
+ o total amount of downloaded data
+ o total amount of uploaded data
+ o number of transfers to perform
+ o number of concurrent transfers being transferred right now
+ o number of transfers queued up waiting to start
+ o total time all transfers are expected to take (if sizes are known)
+ o current time the transfers have spent so far
+ o estimated time left (if sizes are known)
+ o current transfer speed (the faster of UL/DL speeds measured over the last
+ few seconds)
+
+Example:
+
+ DL% UL% Dled Uled Xfers Live Qd Total Current Left Speed
+ 72 -- 37.9G 0 101 30 23 0:00:55 0:00:34 0:00:22 2752M
+
+## Behavior differences
+
+Connections are shared fine between different easy handles, but the
+"authentication contexts" are not. So for example doing HTTP Digest auth with
+one handle for a particular transfer and then continue on with another handle
+that reuses the same connection, the second handle can't send the necessary
+Authorization header at once since the context is only kept in the original
+easy handle.
+
+To fix this, the authorization state could be made possible to share with the
+share API as well, as a context per origin + path (realm?) basically.
+
+Visible in test 153, 1412 and more.
+
+## Feedback!
+
+This is early days for parallel transfer support. Keep your eyes open for
+unintended side effects or downright bugs.
+
+Tell us what you think and how you think we could improve this feature!
+