d1066c9c58
Sample output: > 1..36 > # 1106[lib/setup.c:207] rand seed 1660754406 > TAP version 13 > ok 1 Worst case connect 512 keys: min=0ms max=1ms mean=0.583329ms stddev=0.076376 > ok 2 Connect random-search 512 keys: min=0ms max=1ms mean=0.53412ms stddev=0.0516779 > ok 3 Worst case delete 512 keys: min=2ms max=11ms mean=6.04139ms stddev=0.245792 > ok 4 Add a new key 512 keys: min=0ms max=13ms mean=0.673415ms stddev=0.0820618 > ok 5 Remove random-search 512 keys: min=5ms max=9ms mean=6.65969ms stddev=0.258064 > ok 6 Remove async 512 keys: min=0ms max=0ms mean=0.041825ms stddev=0.0204512 > ok 7 Worst case connect 1024 keys: min=0ms max=2ms mean=0.520357ms stddev=0.0721358 > ok 8 Connect random-search 1024 keys: min=0ms max=2ms mean=0.535312ms stddev=0.0517355 > ok 9 Worst case delete 1024 keys: min=5ms max=9ms mean=8.27219ms stddev=0.287614 > ok 10 Add a new key 1024 keys: min=0ms max=1ms mean=0.688121ms stddev=0.0829531 > ok 11 Remove random-search 1024 keys: min=5ms max=9ms mean=8.37649ms stddev=0.289422 > ok 12 Remove async 1024 keys: min=0ms max=0ms mean=0.0457096ms stddev=0.0213798 > ok 13 Worst case connect 2048 keys: min=0ms max=2ms mean=0.748804ms stddev=0.0865335 > ok 14 Connect random-search 2048 keys: min=0ms max=2ms mean=0.782993ms stddev=0.0625697 > ok 15 Worst case delete 2048 keys: min=5ms max=10ms mean=8.23106ms stddev=0.286898 > ok 16 Add a new key 2048 keys: min=0ms max=1ms mean=0.812988ms stddev=0.0901658 > ok 17 Remove random-search 2048 keys: min=8ms max=9ms mean=8.84949ms stddev=0.297481 > ok 18 Remove async 2048 keys: min=0ms max=0ms mean=0.0297223ms stddev=0.0172402 > ok 19 Worst case connect 4096 keys: min=1ms max=5ms mean=1.53352ms stddev=0.123836 > ok 20 Connect random-search 4096 keys: min=1ms max=5ms mean=1.52226ms stddev=0.0872429 > ok 21 Worst case delete 4096 keys: min=5ms max=9ms mean=8.25874ms stddev=0.28738 > ok 22 Add a new key 4096 keys: min=0ms max=3ms mean=1.67382ms stddev=0.129376 > ok 23 Remove random-search 4096 keys: min=5ms max=10ms mean=8.26178ms stddev=0.287433 > ok 24 Remove async 4096 keys: min=0ms max=0ms mean=0.0340009ms stddev=0.0184393 > ok 25 Worst case connect 8192 keys: min=2ms max=4ms mean=2.86208ms stddev=0.169177 > ok 26 Connect random-search 8192 keys: min=2ms max=4ms mean=2.87592ms stddev=0.119915 > ok 27 Worst case delete 8192 keys: min=6ms max=11ms mean=7.55291ms stddev=0.274826 > ok 28 Add a new key 8192 keys: min=1ms max=5ms mean=2.56797ms stddev=0.160249 > ok 29 Remove random-search 8192 keys: min=5ms max=10ms mean=7.14002ms stddev=0.267208 > ok 30 Remove async 8192 keys: min=0ms max=0ms mean=0.0320066ms stddev=0.0178904 > ok 31 Worst case connect 16384 keys: min=5ms max=6ms mean=5.55334ms stddev=0.235655 > ok 32 Connect random-search 16384 keys: min=5ms max=6ms mean=5.52614ms stddev=0.166225 > ok 33 Worst case delete 16384 keys: min=5ms max=11ms mean=7.39109ms stddev=0.271866 > ok 34 Add a new key 16384 keys: min=2ms max=4ms mean=3.35799ms stddev=0.183248 > ok 35 Remove random-search 16384 keys: min=5ms max=8ms mean=6.86078ms stddev=0.261931 > ok 36 Remove async 16384 keys: min=0ms max=0ms mean=0.0302384ms stddev=0.0173892 > # Totals: pass:36 fail:0 xfail:0 xpass:0 skip:0 error:0 >From the output it's visible that the current simplified approach with linked-list of MKTs scales quite fine even for thousands of keys. And that also means that the majority of the time for delete is eaten by synchronize_rcu() [which I can confirm separately by tracing]. Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.