<div style="color:rgb(34,34,34);font-size:13px;font-family:Tahoma,微软雅黑">I am suffering for slow searching performance on Xapian. </div><div style="color:rgb(34,34,34);font-size:13px;font-family:Tahoma,微软雅黑">
<br></div><div style="color:rgb(34,34,34);font-size:13px;font-family:Tahoma,微软雅黑">I am using Xapian for indexing about 150,000,000 documents.</div><div style="color:rgb(34,34,34);font-size:13px;font-family:Tahoma,微软雅黑">
It was implemented in C++;</div><div style="color:rgb(34,34,34);font-size:13px;font-family:Tahoma,微软雅黑"><br></div><div style><div style="color:rgb(34,34,34);font-family:Tahoma,微软雅黑;font-size:13px">
The performance of searching was not that fast.</div><div style="color:rgb(34,34,34);font-family:Tahoma,微软雅黑;font-size:13px">e.g. Searching a query, which includes about 20 terms, needs 2 secs avg.</div><div style="color:rgb(34,34,34);font-family:Tahoma,微软雅黑;font-size:13px">


<br></div><div><div><div style="color:rgb(34,34,34);font-family:Tahoma,微软雅黑;font-size:13px">For searching, I followed such steps:</div><div><ol style="color:rgb(34,34,34);font-family:Tahoma,微软雅黑;font-size:13px"><li style="margin-left:15px">


construct a QueryParser for certain string</li><li style="margin-left:15px">parse the query to get a Xapian::Query</li><li style="margin-left:15px">construct an Enquire for searching by calling get_mset method</li></ol><font color="#222222" face="Tahoma, 微软雅黑">here is the function-time-cost for searching:</font></div>


</div></div><div><font color="#222222" face="Tahoma, 微软雅黑"><br></font></div><div style="color:rgb(34,34,34);font-family:Tahoma,微软雅黑;font-size:13px"><div>samples  %        symbol name</div><div>75649    28.0401  ChertPostList::move_forward_in_chunk_to_at_least(unsigned int)</div>


<div>30118    11.1635  Xapian::BM25Weight::get_sumpart(unsigned int, unsigned int) const</div><div>21291     7.8917  AndMaybePostList::process_next_or_skip_to(double, Xapian::PostingIterator::Internal*)</div><div>17803     6.5989  OrPostList::next(double)</div>


<div>12481     4.6262  AndMaybePostList::get_weight() const</div><div>10729     3.9768  OrPostList::get_weight() const</div><div>10096     3.7422  AndMaybePostList::next(double)</div><div>8743      3.2407  ChertDatabase::get_doclength(unsigned int) const</div>


<div>7527      2.7900  LeafPostList::get_weight() const</div><div>7504      2.7814  ChertPostListTable::get_doclength(unsigned int, Xapian::Internal::RefCntPtr&lt;ChertDatabase const&gt;) const</div><div>5402      2.0023  ChertPostList::jump_to(unsigned int)</div>


<div>4518      1.6746  ChertPostList::skip_to(unsigned int, double)</div><div>4341      1.6090  ChertPostList::next_in_chunk()</div><div>4207      1.5594  ChertPostList::get_docid() const</div><div>4065      1.5067  ChertPostList::at_end() const</div>


<div>3988      1.4782  AndMaybePostList::at_end() const</div><div>3899      1.4452  OrPostList::get_docid() const</div><div>3655      1.3548  MultiMatch::get_mset(unsigned int, unsigned int, unsigned int, Xapian::MSet&amp;, Xapian::Weight::Internal const&amp;, Xapian::MatchDecider</div>


<div> const*, Xapian::MatchDecider const*, Xapian::KeyMaker const*)</div><div>3172      1.1757  OrPostList::at_end() const</div><div>3061      1.1346  ChertPostList::get_wdf() const</div></div><div style="color:rgb(34,34,34);font-family:Tahoma,微软雅黑;font-size:13px">


<br></div><div style="color:rgb(34,34,34);font-family:Tahoma,微软雅黑;font-size:13px">most of the time cost were about chert post list;</div><div style="color:rgb(34,34,34);font-family:Tahoma,微软雅黑;font-size:13px"><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">

Could I use some separate database for getting faster searching?</blockquote><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">

Compacting database will help? </blockquote><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">How to reduce time cost for chert post list operation?</blockquote>

<div><br></div><div style="color:rgb(34,34,34);font-family:Tahoma,微软雅黑;font-size:13px">
<br></div><div style="color:rgb(34,34,34);font-family:Tahoma,微软雅黑;font-size:13px">Thanks!!</div><div style="color:rgb(34,34,34);font-family:Tahoma,微软雅黑;font-size:13px"><br></div><div style="color:rgb(34,34,34);font-family:Tahoma,微软雅黑;font-size:13px">


De Lin</div></div>