console.log(bulk.length); console.log(new Date()); pos= bulk.indexOf("788bbd6b12d79a4ee18e36a8a264fb496465c71b7932a965ed731397b7c97d14"); console.log(pos); cons

console.log(bulk.length); console.log(new Date()); pos= bulk.indexOf("788bbd6b12d79a4ee18e36a8a264fb496465c71b7932a965ed731397b7c97d14"); console.log(pos); console.log(new Date()); 209715266 debugger eval code:1:1 Date 2018-04-28T00:08:30.231Z debugger eval code:1:27 209715202 debugger eval code:1:139 Date 2018-04-28T00:08:30.252Z debugger eval code:1:157 That's about 0.021 seconds for however Firefox implements String.indexOf(). $ dd if=/dev/urandom of=200mb.dat bs=1M count=200 200+0 records in 200+0 records out 209715200 bytes (210 MB, 200 MiB) copied, 2.98279 s, 70.3 MB/s $ echo 788bbd6b12d79a4ee18e36a8a264fb496465c71b7932a965ed731397b7c97d14 >>200mb.dat $ time grep -o 788bbd6b12d79a4ee18e36a8a264fb496465c71b7932a965ed731397b7c97d14 <200mb.dat Binary file (standard input) matches real 0m0.056s user 0m0.028s sys 0m0.028s That's not too terribly different.