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<div class="textblock"><p>Opening a new cursor is a relatively expensive operation in WiredTiger (especially in table objects and Log-Structured Merge Trees (LSM) trees, where a logical cursor may require multiple, underlying object cursors), and caching cursors can improve performance. On the other hand, cursors hold positions in objects, and therefore long-lived cursor positions can decrease performance by blocking page eviction or looking like a long-lived transaction.</p>
<p>Best practices are to cache cursors, but use the <a class="el" href="struct_w_t___c_u_r_s_o_r.html#afc1b42c22c9c85e1ba08ce3b34437565" title="Reset the cursor. ">WT_CURSOR::reset</a> method to discard the cursor's position in the object when the position is no longer needed. Additionally, use the <a class="el" href="struct_w_t___c_u_r_s_o_r.html#aac90d9fbcc031570f924db55f8a1cee3" title="Insert a record and optionally update an existing record. ">WT_CURSOR::insert</a> method instead of the <a class="el" href="struct_w_t___c_u_r_s_o_r.html#a444cdc0952e7f8d55d23173516c7037f" title="Update an existing record and optionally insert a record. ">WT_CURSOR::update</a> method when there's no need to hold a position in the object, because the <a class="el" href="struct_w_t___c_u_r_s_o_r.html#aac90d9fbcc031570f924db55f8a1cee3" title="Insert a record and optionally update an existing record. ">WT_CURSOR::insert</a> method never holds a cursor position and there's no need to call <a class="el" href="struct_w_t___c_u_r_s_o_r.html#afc1b42c22c9c85e1ba08ce3b34437565" title="Reset the cursor. ">WT_CURSOR::reset</a>. </p>
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