Description:
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When doing loads of INSERT INTO table VALUES (col1,col2,col3,...) VALUES (value1, value2, value3, ....) and the row primary key already exists, the mysql extension leaks memory.  If the row does not exist, the mysql extension does not leak memory.

It uses more than 1.2G+ of RAM.

I've tried using references to the result set etc. and it makes no difference to the memory utilization.

Reproduce code:
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Working on getting reproduce to contain nothing proprietary.

Expected result:
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I would expect it to continue using around 7Mb of RAM, not 1.2Gb+.

Actual result:
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24968 mysql_ad  16   0 1179m 616m 1188 S 19.0 30.4   1:42.77 php
...
24968 mysql_ad  16   0 1211m 649m 1188 S  5.0 32.0   1:45.73 php
...
24968 mysql_ad  16   0 1284m 721m 1188 R 41.0 35.6   1:52.29 php
...
24968 mysql_ad  16   0 1442m 877m 1188 R 20.6 43.3   2:06.87 php
...
24968 mysql_ad  16   0 1554m 847m 1164 S 38.9 41.8   2:16.74 php
...
24968 mysql_ad  16   0 1601m 894m 1164 S 36.6 44.2   2:20.88 php
...
24968 mysql_ad  16   0 1646m 939m 1164 S 46.6 46.3   2:24.70 php
...
24968 mysql_ad  16   0 2304m 904m 1124 S 62.0 44.7   3:19.94 php
...
24968 mysql_ad  16   0 2359m 960m 1124 S 62.5 47.4   3:24.56 php
...
24968 mysql_ad  16   0 2403m 1.0g 1124 S 61.8 49.6   3:28.30 php
...
24968 mysql_ad  16   0 2436m 1.0g 1124 R 64.2 51.2   3:31.10 php
...
24968 mysql_ad  16   0 2481m 1.1g 1124 R 62.5 53.4   3:34.84 php