This way the behavior is very similar to the past one.
This is useful in order to remember the user she probably failed to
configure a password correctly.
Few tests had borderline thresholds that were adjusted.
The slave buffers test had two issues, preventing the slave buffer from growing:
1) the slave didn't necessarily go to sleep on time, or woke up too early,
now using SIGSTOP to make sure it goes to sleep exactly when we want.
2) the master disconnected the slave on timeout
This should be able to find new bugs and regressions about the new
sorted set update function when ZADD is used to update an element
already existing.
The test is able to find the bug fixed at 156f26d0 immediately.
it looks like on slow machines we're getting:
[err]: slave buffer are counted correctly in tests/unit/maxmemory.tcl
Expected condition '$slave_buf > 2*1024*1024' to be true (16914 > 2*1024*1024)
this is a result of the slave waking up too early and eating the
slave buffer before the traffic and the test ends.
on slower machines, the active defrag test tended to fail.
although the fragmentation ratio was below the treshold, the defragger was
still in the middle of a scan cycle.
this commit changes:
- the defragger uses the current fragmentation state, rather than the cache one
that is updated by server cron every 100ms. this actually fixes a bug of
starting one excess scan cycle
- the test lets the defragger use more CPU cycles, in hope that the defrag
will be faster, but also give it more time before we give up.
A) slave buffers didn't count internal fragmentation and sds unused space,
this caused them to induce eviction although we didn't mean for it.
B) slave buffers were consuming about twice the memory of what they actually needed.
- this was mainly due to sdsMakeRoomFor growing to twice as much as needed each time
but networking.c not storing more than 16k (partially fixed recently in 237a38737).
- besides it wasn't able to store half of the new string into one buffer and the
other half into the next (so the above mentioned fix helped mainly for small items).
- lastly, the sds buffers had up to 30% internal fragmentation that was wasted,
consumed but not used.
C) inefficient performance due to starting from a small string and reallocing many times.
what i changed:
- creating dedicated buffers for reply list, counting their size with zmalloc_size
- when creating a new reply node from, preallocate it to at least 16k.
- when appending a new reply to the buffer, first fill all the unused space of the
previous node before starting a new one.
other changes:
- expose mem_not_counted_for_evict info field for the benefit of the test suite
- add a test to make sure slave buffers are counted correctly and that they don't cause eviction
RESTORE now supports:
1. Setting LRU/LFU
2. Absolute-time TTL
Other related changes:
1. RDB loading will not override LRU bits when RDB file
does not contain the LRU opcode.
2. RDB loading will not set LRU/LFU bits if the server's
maxmemory-policy does not match.
